refactor: move buildable .NET source into src/, update CI/doc paths

Groups the repo root into src (buildable source), docs (already existed),
and everything else (db/, scripts/, tests/, deploy/ - deployment/ops/test
assets that aren't compiled, already organized as their own folders). CI
now only needs src/ to build: dotnet restore/build/test/publish all point
at src/TaxBaik.sln, src/TaxBaik.Web/, src/TaxBaik.Proxy/.

- git mv every project (Domain, Infrastructure, Application,
  Application.Tests, Web, Web.Client, Proxy) and TaxBaik.sln into src/ as a
  unit, so relative ProjectReference/.sln paths stay valid unchanged.
- .gitea/workflows/deploy.yml: 6 dotnet restore/clean/build/test/publish
  invocations now point at src/. db/migrations and scripts/ stay at root
  (deploy_gb.sh and browser-e2e.yml only touch published output and the
  deployed URL, not source paths - verified, no changes needed there).
- scripts/validate_admin_render.sh: admin render-mode file paths now
  src/TaxBaik.Web.Client/...
- scripts/validate_kst_timestamps.sh: dropped deploy.sh from its target
  list - that script was removed in the prior cleanup commit (dead, no
  CI workflow referenced it) but this validator still expected it to exist.
- CLAUDE.md, docs/ENGINEERING_HARNESS.md, docs/ADMIN_PATTERN_CRITIQUE_WBS.md:
  updated project-structure diagram, dotnet run/build commands, and grep
  targets to the new src/ paths (also fixed a pre-existing stale path in
  ADMIN_PATTERN_CRITIQUE_WBS.md that still said TaxBaik.Web/Components/Admin
  from before that ever moved to TaxBaik.Web.Client).
- Added a Repo Root harness rule + Architecture Guardrail entries: new files
  belong under src/docs/tests/scripts/db/deploy, not loose at root; temp
  work stays outside the repo (or under a gitignored .scratch/) and is
  never committed.

Verified locally: dotnet build/test src/TaxBaik.sln (26/26 tests), and all
three scripts/validate_*.sh pass against the new layout.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/TaxBaik.Application/Class1.cs

@@ -0,0 +1 @@
+namespace TaxBaik.Application { }

src/TaxBaik.Application/DTOs/AnnouncementDto.cs

@@ -0,0 +1,13 @@
+namespace TaxBaik.Application.DTOs;
+
+public class AnnouncementDto
+{
+    public int Id { get; set; }
+    public string Title { get; set; } = "";
+    public string? Content { get; set; }
+    public string DisplayType { get; set; } = "info";
+    public bool IsActive { get; set; } = true;
+    public DateTime? StartsAt { get; set; }
+    public DateTime? EndsAt { get; set; }
+    public int SortOrder { get; set; }
+}

src/TaxBaik.Application/DTOs/ClientDto.cs

@@ -0,0 +1,30 @@
+namespace TaxBaik.Application.DTOs;
+
+public class ClientDto
+{
+    public int Id { get; set; }
+    public string Name { get; set; } = null!;
+    public string? CompanyName { get; set; }
+    public string? Phone { get; set; }
+    public string? Email { get; set; }
+    public string? ServiceType { get; set; }
+    public string? TaxType { get; set; }
+    public string Status { get; set; } = "active";
+    public string? Source { get; set; }
+    public string? Memo { get; set; }
+    public DateTime CreatedAt { get; set; }
+    public DateTime UpdatedAt { get; set; }
+}
+
+public class CreateClientDto
+{
+    public string Name { get; set; } = null!;
+    public string? CompanyName { get; set; }
+    public string? Phone { get; set; }
+    public string? Email { get; set; }
+    public string? ServiceType { get; set; }
+    public string? TaxType { get; set; }
+    public string Status { get; set; } = "active";
+    public string? Source { get; set; }
+    public string? Memo { get; set; }
+}

src/TaxBaik.Application/DTOs/CreateBlogPostDto.cs

@@ -0,0 +1,32 @@
+namespace TaxBaik.Application.DTOs;
+
+public class CreateBlogPostDto
+{
+    public required string Title { get; set; }
+    public required string Content { get; set; }
+    public int? CategoryId { get; set; }
+    public string? Tags { get; set; }
+    public string? SeoTitle { get; set; }
+    public string? SeoDescription { get; set; }
+    public string? ThumbnailUrl { get; set; }
+    public bool IsPublished { get; set; }
+    public int? AuthorId { get; set; }
+}
+
+public class BlogPostResponseDto
+{
+    public int Id { get; set; }
+    public string Title { get; set; } = string.Empty;
+    public string Content { get; set; } = string.Empty;
+    public int? CategoryId { get; set; }
+    public string? Tags { get; set; }
+    public string? SeoTitle { get; set; }
+    public string? SeoDescription { get; set; }
+    public string? ThumbnailUrl { get; set; }
+    public bool IsPublished { get; set; }
+    public int? AuthorId { get; set; }
+    public int ViewCount { get; set; }
+    public string Slug { get; set; } = string.Empty;
+    public DateTime CreatedAt { get; set; }
+    public DateTime? PublishedAt { get; set; }
+}

src/TaxBaik.Application/DTOs/SubmitInquiryDto.cs

@@ -0,0 +1,11 @@
+namespace TaxBaik.Application.DTOs;
+
+public class SubmitInquiryDto
+{
+    public string Name { get; set; } = string.Empty;
+    public string Phone { get; set; } = string.Empty;
+    public string? Email { get; set; }
+    public string ServiceType { get; set; } = string.Empty;
+    public string Message { get; set; } = string.Empty;
+    public bool SuppressNotification { get; set; }
+}

src/TaxBaik.Application/DTOs/UpdateInquiryDto.cs

@@ -0,0 +1,12 @@
+namespace TaxBaik.Application.DTOs;
+
+public class UpdateInquiryDto
+{
+    public string Name { get; set; } = string.Empty;
+    public string Phone { get; set; } = string.Empty;
+    public string? Email { get; set; }
+    public string ServiceType { get; set; } = string.Empty;
+    public string Message { get; set; } = string.Empty;
+    public string Status { get; set; } = string.Empty;
+    public string? AdminMemo { get; set; }
+}

src/TaxBaik.Application/DependencyInjection.cs

@@ -0,0 +1,33 @@
+namespace TaxBaik.Application;
+
+using Microsoft.Extensions.DependencyInjection;
+using TaxBaik.Application.Services;
+
+public static class DependencyInjection
+{
+    public static IServiceCollection AddApplication(this IServiceCollection services)
+    {
+        services.AddScoped<BlogService>();
+        services.AddScoped<InquiryService>();
+        services.AddScoped<AdminDashboardService>();
+        services.AddScoped<IInquiryNotificationService, NoopInquiryNotificationService>();
+        services.AddScoped<SiteSettingService>();
+        services.AddScoped<CategoryService>();
+        services.AddScoped<AnnouncementService>();
+        services.AddSingleton<SeasonalMarketingService>();
+        services.AddScoped<ClientService>();
+        services.AddScoped<FaqService>();
+        services.AddScoped<ConsultationService>();
+        services.AddScoped<TaxFilingService>();
+        services.AddScoped<CompanyService>();
+        services.AddScoped<TaxProfileService>();
+        services.AddScoped<TaxFilingScheduleService>();
+        services.AddScoped<ConsultingActivityService>();
+        services.AddScoped<ContractService>();
+        services.AddScoped<RevenueTrackingService>();
+        services.AddScoped<TelegramReportService>();
+        services.AddScoped<PortalUserService>();
+        services.AddScoped<CommonCodeService>();
+        return services;
+    }
+}

src/TaxBaik.Application/Seasonal/BusinessDayCalculator.cs

@@ -0,0 +1,74 @@
+namespace TaxBaik.Application.Seasonal;
+
+public static class BusinessDayCalculator
+{
+    private static readonly HashSet<DateOnly> HolidayDates = new()
+    {
+        // 2026
+        new DateOnly(2026, 1, 1),
+        new DateOnly(2026, 2, 16),
+        new DateOnly(2026, 2, 17),
+        new DateOnly(2026, 2, 18),
+        new DateOnly(2026, 3, 1),
+        new DateOnly(2026, 3, 2),
+        new DateOnly(2026, 5, 5),
+        new DateOnly(2026, 5, 25),
+        new DateOnly(2026, 6, 6),
+        new DateOnly(2026, 8, 15),
+        new DateOnly(2026, 8, 16),
+        new DateOnly(2026, 8, 17),
+        new DateOnly(2026, 9, 24),
+        new DateOnly(2026, 9, 25),
+        new DateOnly(2026, 9, 26),
+        new DateOnly(2026, 10, 3),
+        new DateOnly(2026, 10, 4),
+        new DateOnly(2026, 10, 5),
+        new DateOnly(2026, 10, 9),
+        new DateOnly(2026, 12, 25),
+
+        // 2027
+        new DateOnly(2027, 1, 1),
+        new DateOnly(2027, 2, 6),
+        new DateOnly(2027, 2, 7),
+        new DateOnly(2027, 2, 8),
+        new DateOnly(2027, 2, 9),
+        new DateOnly(2027, 3, 1),
+        new DateOnly(2027, 3, 2),
+        new DateOnly(2027, 5, 5),
+        new DateOnly(2027, 5, 13),
+        new DateOnly(2027, 6, 6),
+        new DateOnly(2027, 8, 15),
+        new DateOnly(2027, 8, 16),
+        new DateOnly(2027, 9, 14),
+        new DateOnly(2027, 9, 15),
+        new DateOnly(2027, 9, 16),
+        new DateOnly(2027, 10, 3),
+        new DateOnly(2027, 10, 4),
+        new DateOnly(2027, 10, 9),
+        new DateOnly(2027, 10, 10),
+        new DateOnly(2027, 10, 11),
+        new DateOnly(2027, 12, 25),
+        new DateOnly(2027, 12, 26)
+    };
+
+    public static DateOnly GetEffectiveBusinessDate(DateOnly date)
+    {
+        var effectiveDate = date;
+        while (!IsBusinessDay(effectiveDate))
+        {
+            effectiveDate = effectiveDate.AddDays(1);
+        }
+
+        return effectiveDate;
+    }
+
+    public static int GetBusinessDayDiff(DateOnly date, DateOnly referenceDate)
+    {
+        var effectiveDate = GetEffectiveBusinessDate(date);
+        return effectiveDate.DayNumber - referenceDate.DayNumber;
+    }
+
+    private static bool IsBusinessDay(DateOnly date)
+        => date.DayOfWeek is not DayOfWeek.Saturday and not DayOfWeek.Sunday
+           && !HolidayDates.Contains(date);
+}

src/TaxBaik.Application/Seasonal/CurrentSeasonDto.cs

@@ -0,0 +1,15 @@
+namespace TaxBaik.Application.Seasonal;
+
+public record CurrentSeasonDto
+{
+    public string Key { get; init; } = "";
+    public string Name { get; init; } = "";
+    public string HeroHeadline { get; init; } = "";
+    public string HeroSubtext { get; init; } = "";
+    public string UrgencyBadge { get; init; } = "";
+    public string FocusService { get; init; } = "";
+    public string RelatedCategorySlug { get; init; } = "";
+    public string CtaText { get; init; } = "상담 신청하기";
+    public int DaysUntilDeadline { get; init; }
+    public DateTime Deadline { get; init; }
+}

src/TaxBaik.Application/Seasonal/TaxSeason.cs

@@ -0,0 +1,20 @@
+namespace TaxBaik.Application.Seasonal;
+
+public record TaxSeason
+{
+    public string Key { get; init; } = "";
+    public string Name { get; init; } = "";
+
+    public int StartMonth { get; init; }
+    public int StartDay { get; init; }
+    public int EndMonth { get; init; }
+    public int EndDay { get; init; }
+
+    public string HeroHeadline { get; init; } = "";
+    public string HeroSubtext { get; init; } = "";
+    public string UrgencyBadge { get; init; } = "";
+    public string FocusService { get; init; } = "";
+    public string CtaText { get; init; } = "상담 신청하기";
+    /// <summary>블로그 시즌 연동 시 우선 노출할 카테고리 slug (categories.slug 참조)</summary>
+    public string RelatedCategorySlug { get; init; } = "";
+}

src/TaxBaik.Application/Seasonal/TaxSeasonCalendar.cs

@@ -0,0 +1,103 @@
+namespace TaxBaik.Application.Seasonal;
+
+/// <summary>
+/// 한국 세무사 사무실 연간 시즌 캘린더.
+/// 각 시즌이 활성화되면 홈페이지 Hero가 해당 세무 이벤트에 맞게 전환된다.
+/// </summary>
+public static class TaxSeasonCalendar
+{
+    public static readonly IReadOnlyList<TaxSeason> Seasons =
+    [
+        new TaxSeason
+        {
+            Key = "vat-2nd",
+            Name = "부가가치세 2기 확정신고",
+            StartMonth = 1, StartDay = 1,
+            EndMonth = 1, EndDay = 25,
+            HeroHeadline = "부가가치세 2기\n1월 25일 마감",
+            HeroSubtext = "일반과세 사업자 확정신고 · 기한 내 신고로 가산세 방지",
+            UrgencyBadge = "D-{n}일 | 부가세 마감",
+            FocusService = "business-tax",
+            CtaText = "부가세 신고 상담",
+            RelatedCategorySlug = "vat"
+        },
+        new TaxSeason
+        {
+            Key = "year-end-settlement",
+            Name = "연말정산",
+            StartMonth = 1, StartDay = 15,
+            EndMonth = 2, EndDay = 28,
+            HeroHeadline = "연말정산\n지금 준비하세요",
+            HeroSubtext = "직원이 있는 사업자 원천징수 신고 · 환급 최대화",
+            UrgencyBadge = "연말정산 진행 중",
+            FocusService = "business-tax",
+            CtaText = "연말정산 상담",
+            RelatedCategorySlug = "business-tax"
+        },
+        new TaxSeason
+        {
+            Key = "corporate-tax",
+            Name = "법인세 신고",
+            StartMonth = 3, StartDay = 1,
+            EndMonth = 3, EndDay = 31,
+            HeroHeadline = "법인세\n3월 31일 마감",
+            HeroSubtext = "법인사업자 결산 · 세무조정 · 절세 전략 수립",
+            UrgencyBadge = "D-{n}일 | 법인세 마감",
+            FocusService = "business-tax",
+            CtaText = "법인세 신고 상담",
+            RelatedCategorySlug = "business-tax"
+        },
+        new TaxSeason
+        {
+            Key = "income-tax",
+            Name = "종합소득세 신고",
+            StartMonth = 5, StartDay = 1,
+            EndMonth = 5, EndDay = 31,
+            HeroHeadline = "종합소득세\n5월 31일 마감",
+            HeroSubtext = "개인사업자 · 임대소득 · 프리랜서 · 기타소득 모두 해당",
+            UrgencyBadge = "D-{n}일 | 종합소득세 마감",
+            FocusService = "business-tax",
+            CtaText = "종합소득세 상담",
+            RelatedCategorySlug = "income-tax"
+        },
+        new TaxSeason
+        {
+            Key = "vat-1st",
+            Name = "부가가치세 1기 확정신고",
+            StartMonth = 7, StartDay = 1,
+            EndMonth = 7, EndDay = 25,
+            HeroHeadline = "부가가치세 1기\n7월 27일 마감",
+            HeroSubtext = "일반과세 사업자 1기 확정신고 · 매입세액 공제 점검",
+            UrgencyBadge = "D-{n}일 | 부가세 마감",
+            FocusService = "business-tax",
+            CtaText = "부가세 신고 상담",
+            RelatedCategorySlug = "vat"
+        },
+        new TaxSeason
+        {
+            Key = "comprehensive-real-estate-tax",
+            Name = "종합부동산세",
+            StartMonth = 11, StartDay = 15,
+            EndMonth = 11, EndDay = 30,
+            HeroHeadline = "종합부동산세\n납부 시즌",
+            HeroSubtext = "다주택자 · 임대사업자 세부담 분석 · 분납·합산배제 검토",
+            UrgencyBadge = "D-{n}일 | 종부세 납부",
+            FocusService = "real-estate-tax",
+            CtaText = "종부세 절세 상담",
+            RelatedCategorySlug = "real-estate-tax"
+        },
+        new TaxSeason
+        {
+            Key = "year-end-gift",
+            Name = "연말 증여·절세 플래닝",
+            StartMonth = 12, StartDay = 1,
+            EndMonth = 12, EndDay = 31,
+            HeroHeadline = "연말 절세 플래닝\n마지막 기회",
+            HeroSubtext = "증여 공제 한도 · 자산 이전 · 법인전환 연간 마감",
+            UrgencyBadge = "D-{n}일 | 연간 증여 한도 마감",
+            FocusService = "family-asset",
+            CtaText = "연말 절세 상담",
+            RelatedCategorySlug = "family-asset"
+        }
+    ];
+}

src/TaxBaik.Application/Services/AdminDashboardService.cs

@@ -0,0 +1,87 @@
+namespace TaxBaik.Application.Services;
+
+using Microsoft.Extensions.Caching.Memory;
+using TaxBaik.Domain.Entities;
+
+public record AdminDashboardSummary(
+    int ThisMonthInquiries,
+    int NewInquiries,
+    int TotalPosts,
+    int PublishedPosts,
+    IReadOnlyList<Inquiry> RecentInquiries);
+
+public class AdminDashboardService(
+    InquiryService inquiryService,
+    BlogService blogService,
+    IMemoryCache memoryCache)
+{
+    private static readonly TimeSpan CacheDuration = TimeSpan.FromSeconds(30);
+    public const string CacheKey = "admin-dashboard-summary";
+
+    public async Task<AdminDashboardSummary> GetSummaryAsync(CancellationToken ct = default)
+    {
+        if (memoryCache.TryGetValue(CacheKey, out AdminDashboardSummary? cached) && cached != null)
+            return cached;
+
+        var recentTask = inquiryService.GetPagedAsync(1, 5, ct: ct);
+        var thisMonthTask = inquiryService.CountThisMonthAsync(ct);
+        var newTask = inquiryService.CountByStatusAsync("new", ct);
+        var statsTask = blogService.GetStatsAsync(ct);
+
+        var (recentInquiries, _) = await recentTask;
+        var stats = await statsTask;
+        var summary = new AdminDashboardSummary(
+            ThisMonthInquiries: await thisMonthTask,
+            NewInquiries: await newTask,
+            TotalPosts: stats.TotalPosts,
+            PublishedPosts: stats.PublishedPosts,
+            RecentInquiries: recentInquiries.OrderByDescending(x => x.CreatedAt).Take(5).ToList());
+
+        memoryCache.Set(CacheKey, summary, CacheDuration);
+        return summary;
+    }
+
+    /// <summary>
+    /// 최근 문의 조회
+    /// </summary>
+    public async Task<IReadOnlyList<Inquiry>> GetRecentInquiriesAsync(int limit, CancellationToken ct = default)
+    {
+        var (inquiries, _) = await inquiryService.GetPagedAsync(1, limit, ct: ct);
+        return inquiries.OrderByDescending(x => x.CreatedAt).ToList();
+    }
+
+    /// <summary>
+    /// 월별 통계 (접수 건수, 진행 중, 완료)
+    /// </summary>
+    public async Task<object> GetMonthlyStatsAsync(string? month, CancellationToken ct = default)
+    {
+        var targetMonth = month != null && DateTime.TryParse($"{month}-01", out var dt)
+            ? dt
+            : DateTime.Today;
+
+        var startDate = new DateTime(targetMonth.Year, targetMonth.Month, 1);
+        var endDate = startDate.AddMonths(1).AddDays(-1);
+
+        // 캐시 시도 (일 단위)
+        var cacheKey = $"admin-stats-{startDate:yyyy-MM}";
+        if (memoryCache.TryGetValue(cacheKey, out object? cachedStats) && cachedStats != null)
+            return cachedStats;
+
+        var total = await inquiryService.CountByDateRangeAsync(startDate, endDate, ct);
+        var consulting = await inquiryService.CountByStatusAndDateAsync("consulting", startDate, endDate, ct);
+        var completed = await inquiryService.CountByStatusAndDateAsync("contracted", startDate, endDate, ct);
+
+        var result = new
+        {
+            month = startDate.ToString("yyyy-MM"),
+            totalInquiries = total,
+            consultingCount = consulting,
+            completedCount = completed,
+            newCount = total - consulting - completed,
+            completionRate = total > 0 ? (completed * 100.0 / total) : 0.0
+        };
+
+        memoryCache.Set(cacheKey, result, TimeSpan.FromHours(1));
+        return result;
+    }
+}

src/TaxBaik.Application/Services/AnnouncementService.cs

@@ -0,0 +1,44 @@
+namespace TaxBaik.Application.Services;
+
+using TaxBaik.Application.DTOs;
+using TaxBaik.Domain.Entities;
+using TaxBaik.Domain.Interfaces;
+
+public class AnnouncementService(IAnnouncementRepository repository)
+{
+    public Task<IEnumerable<Announcement>> GetActiveAsync(CancellationToken ct = default)
+        => repository.GetActiveAsync(ct);
+
+    public Task<IEnumerable<Announcement>> GetAllAsync(CancellationToken ct = default)
+        => repository.GetAllAsync(ct);
+
+    public Task<Announcement?> GetByIdAsync(int id, CancellationToken ct = default)
+        => repository.GetByIdAsync(id, ct);
+
+    public Task<int> CreateAsync(AnnouncementDto dto, CancellationToken ct = default)
+    {
+        var entity = MapToEntity(dto);
+        return repository.CreateAsync(entity, ct);
+    }
+
+    public Task UpdateAsync(AnnouncementDto dto, CancellationToken ct = default)
+    {
+        var entity = MapToEntity(dto);
+        return repository.UpdateAsync(entity, ct);
+    }
+
+    public Task DeleteAsync(int id, CancellationToken ct = default)
+        => repository.DeleteAsync(id, ct);
+
+    private static Announcement MapToEntity(AnnouncementDto dto) => new()
+    {
+        Id = dto.Id,
+        Title = dto.Title.Trim(),
+        Content = string.IsNullOrWhiteSpace(dto.Content) ? null : dto.Content.Trim(),
+        DisplayType = dto.DisplayType,
+        IsActive = dto.IsActive,
+        StartsAt = dto.StartsAt,
+        EndsAt = dto.EndsAt,
+        SortOrder = dto.SortOrder
+    };
+}

src/TaxBaik.Application/Services/BlogService.cs

@@ -0,0 +1,183 @@
+namespace TaxBaik.Application.Services;
+
+using System.Text.RegularExpressions;
+using TaxBaik.Application.DTOs;
+using TaxBaik.Domain.Entities;
+using TaxBaik.Domain.Interfaces;
+
+using Microsoft.Extensions.Caching.Memory;
+
+public class BlogService(IBlogPostRepository repository, IMemoryCache memoryCache)
+{
+    public async Task<BlogPost?> GetByIdAsync(int id, CancellationToken ct = default) =>
+        await repository.GetByIdAsync(id, ct);
+
+    public async Task<BlogPost?> GetBySlugAsync(string slug, CancellationToken ct = default) =>
+        await repository.GetBySlugAsync(slug, ct);
+
+    /// <summary>카테고리 슬러그 기준 시즌 관련 글 조회. 부족 시 최신 글로 채워 total개 반환.</summary>
+    public async Task<(IEnumerable<BlogPost> Seasonal, IEnumerable<BlogPost> Latest)> GetSeasonalPostsAsync(
+        string categorySlug, int seasonalCount, int totalCount, CancellationToken ct = default)
+    {
+        var seasonal = (await repository.GetByCategorySlugAsync(categorySlug, seasonalCount, ct)).ToList();
+        var seasonalIds = seasonal.Select(p => p.Id).ToHashSet();
+
+        var (latestAll, _) = await repository.GetPublishedPagedAsync(1, totalCount + seasonalCount, null, ct);
+        var latest = latestAll.Where(p => !seasonalIds.Contains(p.Id)).Take(totalCount - seasonal.Count).ToList();
+
+        return (seasonal, latest);
+    }
+
+    public async Task<(IEnumerable<BlogPost>, int)> GetPublishedPagedAsync(
+        int page, int pageSize, int? categoryId = null, CancellationToken ct = default) =>
+        await repository.GetPublishedPagedAsync(NormalizePage(page), NormalizePageSize(pageSize), categoryId, ct);
+
+    public async Task<IEnumerable<BlogPost>> GetAllAsync(CancellationToken ct = default) =>
+        await repository.GetAllForAdminAsync(ct);
+
+    public async Task<IEnumerable<BlogPost>> GetAllForAdminAsync(CancellationToken ct = default) =>
+        await repository.GetAllForAdminAsync(ct);
+
+    public async Task<(IEnumerable<BlogPost>, int)> GetAdminPagedAsync(
+        int page, int pageSize, CancellationToken ct = default) =>
+        await repository.GetAdminPagedAsync(NormalizePage(page), NormalizePageSize(pageSize), ct);
+
+    public async Task<(IEnumerable<BlogPost>, int)> GetArchivedPagedAsync(
+        int page, int pageSize, CancellationToken ct = default) =>
+        await repository.GetArchivedPagedAsync(NormalizePage(page), NormalizePageSize(pageSize), ct);
+
+    public async Task<int> CreateAsync(BlogPost post, CancellationToken ct = default)
+    {
+        ValidatePost(post);
+        post.Title = post.Title.Trim();
+        post.Content = post.Content.Trim();
+        post.Slug = await GenerateUniqueSlugAsync(post.Title, ct: ct);
+        post.PublishedAt = post.IsPublished ? DateTime.UtcNow : null;
+        var result = await repository.CreateAsync(post, ct);
+        memoryCache.Remove(AdminDashboardService.CacheKey);
+        return result;
+    }
+
+    public async Task<BlogPost> CreateAsync(CreateBlogPostDto dto, CancellationToken ct = default)
+    {
+        var post = new BlogPost
+        {
+            Title = dto.Title,
+            Content = dto.Content,
+            CategoryId = dto.CategoryId,
+            Tags = dto.Tags,
+            SeoTitle = dto.SeoTitle,
+            SeoDescription = dto.SeoDescription,
+            ThumbnailUrl = dto.ThumbnailUrl,
+            IsPublished = dto.IsPublished,
+            AuthorId = dto.AuthorId,
+            CreatedAt = DateTime.UtcNow
+        };
+
+        var id = await CreateAsync(post, ct);
+        post.Id = id;
+        return post;
+    }
+
+    public async Task UpdateAsync(BlogPost post, CancellationToken ct = default)
+    {
+        await repository.UpdateAsync(post, ct);
+        memoryCache.Remove(AdminDashboardService.CacheKey);
+    }
+
+    public async Task<BlogPost?> UpdateAsync(int id, CreateBlogPostDto dto, CancellationToken ct = default)
+    {
+        var post = await repository.GetByIdAsync(id, ct);
+        if (post == null)
+            return null;
+
+        post.Title = dto.Title;
+        post.Content = dto.Content;
+        post.CategoryId = dto.CategoryId;
+        post.Tags = dto.Tags;
+        post.SeoTitle = dto.SeoTitle;
+        post.SeoDescription = dto.SeoDescription;
+        post.ThumbnailUrl = dto.ThumbnailUrl;
+        post.IsPublished = dto.IsPublished;
+        post.PublishedAt = dto.IsPublished
+            ? post.PublishedAt ?? DateTime.UtcNow
+            : null;
+        ValidatePost(post);
+
+        await UpdateAsync(post, ct);
+        return post;
+    }
+
+    public async Task DeleteAsync(int id, CancellationToken ct = default)
+    {
+        await repository.DeleteAsync(id, ct);
+        memoryCache.Remove(AdminDashboardService.CacheKey);
+    }
+
+    public async Task ArchiveAsync(int id, CancellationToken ct = default)
+    {
+        await repository.ArchiveAsync(id, ct);
+        memoryCache.Remove(AdminDashboardService.CacheKey);
+    }
+
+    public async Task RestoreAsync(int id, CancellationToken ct = default)
+    {
+        await repository.RestoreAsync(id, ct);
+        memoryCache.Remove(AdminDashboardService.CacheKey);
+    }
+
+    public async Task IncrementViewCountAsync(int id, CancellationToken ct = default) =>
+        await repository.IncrementViewCountAsync(id, ct);
+
+    private static string GenerateSlug(string title)
+    {
+        var slug = Regex.Replace(title.ToLowerInvariant(), @"[^\w\s-]", "");
+        slug = Regex.Replace(slug, @"\s+", "-");
+        slug = Regex.Replace(slug, @"-+", "-").Trim('-');
+        if (string.IsNullOrWhiteSpace(slug))
+            slug = $"post-{DateTime.UtcNow:yyyyMMddHHmmss}";
+        return slug.Length > 100 ? slug[..100] : slug;
+    }
+
+    private async Task<string> GenerateUniqueSlugAsync(string title, int? existingPostId = null, CancellationToken ct = default)
+    {
+        var baseSlug = GenerateSlug(title);
+        var slug = baseSlug;
+        var suffix = 2;
+        var allPosts = (await repository.GetAllForAdminAsync(ct)).ToList();
+
+        while (allPosts.Any(x => x.Id != existingPostId && string.Equals(x.Slug, slug, StringComparison.OrdinalIgnoreCase)))
+        {
+            var suffixText = $"-{suffix++}";
+            var maxBaseLength = Math.Max(1, 100 - suffixText.Length);
+            slug = $"{baseSlug[..Math.Min(baseSlug.Length, maxBaseLength)]}{suffixText}";
+        }
+
+        return slug;
+    }
+
+    private static void ValidatePost(BlogPost post)
+    {
+        if (string.IsNullOrWhiteSpace(post.Title))
+            throw new ValidationException("제목을 입력하세요.");
+
+        if (string.IsNullOrWhiteSpace(post.Content))
+            throw new ValidationException("본문을 입력하세요.");
+
+        if (post.IsPublished && string.IsNullOrWhiteSpace(post.SeoTitle))
+            throw new ValidationException("발행하려면 SEO 제목을 입력하세요.");
+
+        if (post.IsPublished && string.IsNullOrWhiteSpace(post.SeoDescription))
+            throw new ValidationException("발행하려면 SEO 설명을 입력하세요.");
+    }
+
+    private static int NormalizePage(int page) => Math.Max(1, page);
+
+    private static int NormalizePageSize(int pageSize) => Math.Clamp(pageSize, 1, 100);
+
+    public async Task<(int TotalPosts, int PublishedPosts)> GetStatsAsync(CancellationToken ct = default)
+    {
+        var posts = (await repository.GetAllForAdminAsync(ct)).ToList();
+        return (posts.Count, posts.Count(x => x.IsPublished));
+    }
+}

src/TaxBaik.Application/Services/CategoryService.cs

@@ -0,0 +1,54 @@
+namespace TaxBaik.Application.Services;
+
+using System.Text.RegularExpressions;
+using TaxBaik.Domain.Entities;
+using TaxBaik.Domain.Interfaces;
+
+public class CategoryService(ICategoryRepository repository)
+{
+    public async Task<IEnumerable<Category>> GetAllAsync(CancellationToken ct = default) =>
+        await repository.GetAllAsync(ct);
+
+    public async Task<Category?> GetBySlugAsync(string slug, CancellationToken ct = default) =>
+        await repository.GetBySlugAsync(slug, ct);
+
+    public async Task<Category?> GetByIdAsync(int id, CancellationToken ct = default) =>
+        await repository.GetByIdAsync(id, ct);
+
+    public async Task<Category> CreateAsync(string name, string? description, CancellationToken ct = default)
+    {
+        var slug = GenerateSlug(name);
+        var category = new Category
+        {
+            Name = name.Trim(),
+            Slug = slug,
+            SortOrder = 0
+        };
+
+        var id = await repository.CreateAsync(category, ct);
+        return new Category { Id = id, Name = category.Name, Slug = category.Slug, SortOrder = category.SortOrder };
+    }
+
+    public async Task<Category?> UpdateAsync(int id, string name, string? description, CancellationToken ct = default)
+    {
+        var category = await repository.GetByIdAsync(id, ct);
+        if (category == null)
+            return null;
+
+        category.Name = name.Trim();
+        category.Slug = GenerateSlug(name);
+        await repository.UpdateAsync(category, ct);
+        return category;
+    }
+
+    public async Task DeleteAsync(int id, CancellationToken ct = default) =>
+        await repository.DeleteAsync(id, ct);
+
+    private static string GenerateSlug(string name)
+    {
+        var slug = Regex.Replace(name.ToLowerInvariant(), @"[^\w\s-]", "");
+        slug = Regex.Replace(slug, @"\s+", "-");
+        slug = Regex.Replace(slug, @"-+", "-").Trim('-');
+        return slug.Length > 100 ? slug[..100] : slug;
+    }
+}

src/TaxBaik.Application/Services/ClientService.cs

@@ -0,0 +1,82 @@
+namespace TaxBaik.Application.Services;
+
+using TaxBaik.Application.DTOs;
+using TaxBaik.Domain.Entities;
+using TaxBaik.Domain.Interfaces;
+
+public class ClientService(IClientRepository repository)
+{
+    public async Task<(IEnumerable<Client> Items, int Total)> GetPagedAsync(
+        int page, int pageSize, string? status = null, string? search = null, CancellationToken ct = default) =>
+        await repository.GetPagedAsync(Math.Max(1, page), Math.Clamp(pageSize, 1, 100), status, search, ct);
+
+    public async Task<Client?> GetByIdAsync(int id, CancellationToken ct = default) =>
+        await repository.GetByIdAsync(id, ct);
+
+    public async Task<Client?> GetByEmailAsync(string email, CancellationToken ct = default) =>
+        await repository.GetByEmailAsync(email, ct);
+
+    public async Task<Client?> GetByPhoneAsync(string phone, CancellationToken ct = default) =>
+        await repository.GetByPhoneAsync(phone, ct);
+
+    public async Task<int> CountCreatedAtRangeAsync(DateTime startDateUtc, DateTime endDateUtc, CancellationToken ct = default) =>
+        await repository.CountByCreatedAtRangeAsync(startDateUtc, endDateUtc, ct);
+
+    public async Task<int> CreateAsync(CreateClientDto dto, CancellationToken ct = default)
+    {
+        if (string.IsNullOrWhiteSpace(dto.Name))
+            throw new ValidationException("고객명을 입력하세요.");
+
+        var client = new Client
+        {
+            Name = dto.Name.Trim(),
+            CompanyName = dto.CompanyName?.Trim(),
+            Phone = dto.Phone?.Trim(),
+            Email = dto.Email?.Trim(),
+            ServiceType = dto.ServiceType,
+            TaxType = dto.TaxType,
+            Status = dto.Status,
+            Source = dto.Source,
+            Memo = dto.Memo?.Trim()
+        };
+
+        return await repository.CreateAsync(client, ct);
+    }
+
+    public async Task UpdateAsync(int id, CreateClientDto dto, CancellationToken ct = default)
+    {
+        if (string.IsNullOrWhiteSpace(dto.Name))
+            throw new ValidationException("고객명을 입력하세요.");
+
+        var client = await repository.GetByIdAsync(id, ct)
+            ?? throw new KeyNotFoundException($"고객 ID {id}를 찾을 수 없습니다.");
+
+        client.Name = dto.Name.Trim();
+        client.CompanyName = dto.CompanyName?.Trim();
+        client.Phone = dto.Phone?.Trim();
+        client.Email = dto.Email?.Trim();
+        client.ServiceType = dto.ServiceType;
+        client.TaxType = dto.TaxType;
+        client.Status = dto.Status;
+        client.Source = dto.Source;
+        client.Memo = dto.Memo?.Trim();
+
+        await repository.UpdateAsync(client, ct);
+    }
+
+    public async Task<int> CreateFromInquiryAsync(string name, string? phone, string? serviceType, CancellationToken ct = default)
+    {
+        var client = new Client
+        {
+            Name = name.Trim(),
+            Phone = phone?.Trim(),
+            ServiceType = serviceType,
+            Status = "active",
+            Source = "홈페이지문의"
+        };
+        return await repository.CreateAsync(client, ct);
+    }
+
+    public async Task DeleteAsync(int id, CancellationToken ct = default) =>
+        await repository.DeleteAsync(id, ct);
+}

src/TaxBaik.Application/Services/CommonCodeService.cs

@@ -0,0 +1,67 @@
+using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
+using TaxBaik.Domain.Entities;
+using TaxBaik.Domain.Interfaces;
+
+namespace TaxBaik.Application.Services;
+
+public class CommonCodeService(ICommonCodeRepository commonCodeRepository)
+{
+    private const int MaxCodeGroupLength = 80;
+    private const int MaxCodeValueLength = 120;
+    private const int MaxCodeNameLength = 200;
+
+    public async Task<IEnumerable<string>> GetAllGroupsAsync(CancellationToken ct = default)
+    {
+        return await commonCodeRepository.GetAllGroupsAsync(ct);
+    }
+
+    public async Task<IEnumerable<CommonCode>> GetByGroupAsync(string codeGroup, CancellationToken ct = default)
+    {
+        return await commonCodeRepository.GetByGroupAsync(codeGroup, ct);
+    }
+
+    public async Task<IEnumerable<CommonCode>> GetAllActiveAsync(CancellationToken ct = default)
+    {
+        return await commonCodeRepository.GetAllActiveAsync(ct);
+    }
+
+    public async Task<CommonCode?> GetAsync(string codeGroup, string codeValue, CancellationToken ct = default)
+    {
+        return await commonCodeRepository.GetAsync(codeGroup, codeValue, ct);
+    }
+
+    public async Task UpsertAsync(CommonCode code, CancellationToken ct = default)
+    {
+        Normalize(code);
+        await commonCodeRepository.UpsertAsync(code, ct);
+    }
+
+    public async Task DeleteAsync(string codeGroup, string codeValue, CancellationToken ct = default)
+    {
+        await commonCodeRepository.DeleteAsync(NormalizeToken(codeGroup, nameof(codeGroup), MaxCodeGroupLength), NormalizeToken(codeValue, nameof(codeValue), MaxCodeValueLength), ct);
+    }
+
+    private static void Normalize(CommonCode code)
+    {
+        code.CodeGroup = NormalizeToken(code.CodeGroup, nameof(code.CodeGroup), MaxCodeGroupLength, disallowWhitespace: true);
+        code.CodeValue = NormalizeToken(code.CodeValue, nameof(code.CodeValue), MaxCodeValueLength, disallowWhitespace: true);
+        code.CodeName = NormalizeToken(code.CodeName, nameof(code.CodeName), MaxCodeNameLength);
+    }
+
+    private static string NormalizeToken(string value, string fieldName, int maxLength, bool disallowWhitespace = false)
+    {
+        var normalized = (value ?? string.Empty).Trim();
+        if (string.IsNullOrWhiteSpace(normalized))
+            throw new ValidationException($"{fieldName}은(는) 필수입니다.");
+
+        if (normalized.Length > maxLength)
+            throw new ValidationException($"{fieldName}은(는) 최대 {maxLength}자까지 입력할 수 있습니다.");
+
+        if (disallowWhitespace && normalized.Any(char.IsWhiteSpace))
+            throw new ValidationException($"{fieldName}에는 공백을 사용할 수 없습니다.");
+
+        return normalized;
+    }
+}

src/TaxBaik.Application/Services/CompanyService.cs

@@ -0,0 +1,95 @@
+namespace TaxBaik.Application.Services;
+
+using TaxBaik.Domain.Entities;
+using TaxBaik.Domain.Interfaces;
+
+public class CompanyService(ICompanyRepository repository)
+{
+    public async Task<int> CreateAsync(string companyCode, string companyName, string? contactPerson = null,
+        string? phone = null, string? email = null, string? memo = null, CancellationToken ct = default)
+    {
+        if (string.IsNullOrWhiteSpace(companyCode))
+            throw new ValidationException("회사 코드를 입력하세요.");
+
+        if (string.IsNullOrWhiteSpace(companyName))
+            throw new ValidationException("회사명을 입력하세요.");
+
+        var existing = await repository.GetByCodeAsync(companyCode.Trim(), ct);
+        if (existing != null)
+            throw new ValidationException("이미 존재하는 회사 코드입니다.");
+
+        var company = new Company
+        {
+            CompanyCode = companyCode.Trim(),
+            CompanyName = companyName.Trim(),
+            ContactPerson = string.IsNullOrWhiteSpace(contactPerson) ? null : contactPerson.Trim(),
+            Phone = string.IsNullOrWhiteSpace(phone) ? null : phone.Trim(),
+            Email = string.IsNullOrWhiteSpace(email) ? null : email.Trim(),
+            Memo = string.IsNullOrWhiteSpace(memo) ? null : memo.Trim(),
+            IsActive = true,
+            CreatedAt = DateTime.UtcNow,
+            UpdatedAt = DateTime.UtcNow
+        };
+
+        return await repository.CreateAsync(company, ct);
+    }
+
+    public async Task<Company?> GetByIdAsync(int id, CancellationToken ct = default) =>
+        await repository.GetByIdAsync(id, ct);
+
+    public async Task<Company?> GetByCodeAsync(string code, CancellationToken ct = default) =>
+        await repository.GetByCodeAsync(code, ct);
+
+    public async Task<IEnumerable<Company>> GetAllActiveAsync(CancellationToken ct = default) =>
+        await repository.GetAllActiveAsync(ct);
+
+    public async Task<(IEnumerable<Company>, int)> GetPagedAsync(int page, int pageSize, CancellationToken ct = default)
+    {
+        var (items, total) = await repository.GetPagedAsync(NormalizePage(page), NormalizePageSize(pageSize), ct);
+        return (items, total);
+    }
+
+    public async Task UpdateAsync(int id, string companyCode, string companyName, string? contactPerson = null,
+        string? phone = null, string? email = null, string? memo = null, bool isActive = true, CancellationToken ct = default)
+    {
+        if (string.IsNullOrWhiteSpace(companyCode))
+            throw new ValidationException("회사 코드를 입력하세요.");
+
+        if (string.IsNullOrWhiteSpace(companyName))
+            throw new ValidationException("회사명을 입력하세요.");
+
+        var company = await repository.GetByIdAsync(id, ct);
+        if (company == null)
+            throw new ValidationException("회사를 찾을 수 없습니다.");
+
+        var existing = await repository.GetByCodeAsync(companyCode.Trim(), ct);
+        if (existing != null && existing.Id != id)
+            throw new ValidationException("이미 존재하는 회사 코드입니다.");
+
+        company.CompanyCode = companyCode.Trim();
+        company.CompanyName = companyName.Trim();
+        company.ContactPerson = string.IsNullOrWhiteSpace(contactPerson) ? null : contactPerson.Trim();
+        company.Phone = string.IsNullOrWhiteSpace(phone) ? null : phone.Trim();
+        company.Email = string.IsNullOrWhiteSpace(email) ? null : email.Trim();
+        company.Memo = string.IsNullOrWhiteSpace(memo) ? null : memo.Trim();
+        company.IsActive = isActive;
+        company.UpdatedAt = DateTime.UtcNow;
+
+        await repository.UpdateAsync(company, ct);
+    }
+
+    public async Task DeleteAsync(int id, CancellationToken ct = default)
+    {
+        var company = await repository.GetByIdAsync(id, ct);
+        if (company == null)
+            throw new ValidationException("회사를 찾을 수 없습니다.");
+
+        if (company.CompanyCode == "DEFAULT")
+            throw new ValidationException("기본 회사는 삭제할 수 없습니다.");
+
+        await repository.DeleteAsync(id, ct);
+    }
+
+    private static int NormalizePage(int page) => Math.Max(1, page);
+    private static int NormalizePageSize(int pageSize) => Math.Clamp(pageSize, 1, 100);
+}

src/TaxBaik.Application/Services/ConsultationService.cs

@@ -0,0 +1,25 @@
+namespace TaxBaik.Application.Services;
+
+using TaxBaik.Domain.Entities;
+using TaxBaik.Domain.Interfaces;
+
+public class ConsultationService(IConsultationRepository repository)
+{
+    public static readonly string[] Results =
+        ["상담 중", "계약 완료", "보류", "거절", "완료"];
+
+    public async Task<IEnumerable<Consultation>> GetByClientIdAsync(int clientId, CancellationToken ct = default) =>
+        await repository.GetByClientIdAsync(clientId, ct);
+
+    public async Task<int> CreateAsync(Consultation consultation, CancellationToken ct = default)
+    {
+        if (string.IsNullOrWhiteSpace(consultation.Summary))
+            throw new ValidationException("상담 내용을 입력하세요.");
+        if (consultation.ClientId <= 0)
+            throw new ValidationException("고객을 선택하세요.");
+        return await repository.CreateAsync(consultation, ct);
+    }
+
+    public async Task DeleteAsync(int id, CancellationToken ct = default) =>
+        await repository.DeleteAsync(id, ct);
+}

src/TaxBaik.Application/Services/ConsultingActivityService.cs

@@ -0,0 +1,50 @@
+namespace TaxBaik.Application.Services;
+
+using TaxBaik.Domain.Entities;
+using TaxBaik.Domain.Interfaces;
+
+public class ConsultingActivityService(IConsultingActivityRepository repository)
+{
+    public async Task<int> CreateAsync(int clientId, string activityType, DateTime activityDate,
+        string description, int? consultantId = null, DateTime? nextFollowupDate = null, CancellationToken ct = default)
+    {
+        if (clientId <= 0)
+            throw new ValidationException("유효한 고객을 선택하세요.");
+        if (string.IsNullOrWhiteSpace(activityType))
+            throw new ValidationException("활동 유형을 입력하세요.");
+        if (string.IsNullOrWhiteSpace(description))
+            throw new ValidationException("활동 내용을 입력하세요.");
+
+        var activity = new ConsultingActivity
+        {
+            ClientId = clientId,
+            ActivityType = activityType.Trim(),
+            ActivityDate = activityDate,
+            Description = description.Trim(),
+            AssignedConsultantId = consultantId,
+            NextFollowupDate = nextFollowupDate,
+            CreatedAt = DateTime.UtcNow,
+            UpdatedAt = DateTime.UtcNow
+        };
+
+        return await repository.CreateAsync(activity, ct);
+    }
+
+    public async Task<IEnumerable<ConsultingActivity>> GetByClientIdAsync(int clientId, CancellationToken ct = default) =>
+        await repository.GetByClientIdAsync(clientId, ct);
+
+    public async Task<IEnumerable<ConsultingActivity>> GetAllAsync(CancellationToken ct = default) =>
+        await repository.GetAllAsync(ct);
+
+    public async Task<IEnumerable<ConsultingActivity>> GetPendingFollowupsAsync(CancellationToken ct = default) =>
+        await repository.GetPendingFollowupsAsync(ct);
+
+    public async Task<IEnumerable<ConsultingActivity>> GetConsultantActivityAsync(int consultantId, DateTime fromDate, CancellationToken ct = default) =>
+        await repository.GetByConsultantAsync(consultantId, fromDate, ct);
+
+    public async Task UpdateAsync(int id, string? outcome, DateTime? nextFollowupDate, CancellationToken ct = default)
+    {
+        var activity = new ConsultingActivity { Id = id, Outcome = outcome, NextFollowupDate = nextFollowupDate, UpdatedAt = DateTime.UtcNow };
+        await repository.UpdateAsync(activity, ct);
+    }
+}

src/TaxBaik.Application/Services/ContractService.cs

@@ -0,0 +1,53 @@
+namespace TaxBaik.Application.Services;
+
+using TaxBaik.Domain.Entities;
+using TaxBaik.Domain.Interfaces;
+
+public class ContractService(IContractRepository repository)
+{
+    public async Task<int> CreateAsync(int clientId, string contractNumber, string serviceType,
+        DateTime startDate, decimal? monthlyFee = null, decimal? totalAmount = null, CancellationToken ct = default)
+    {
+        if (clientId <= 0)
+            throw new ValidationException("유효한 고객을 선택하세요.");
+        if (string.IsNullOrWhiteSpace(contractNumber))
+            throw new ValidationException("계약 번호를 입력하세요.");
+        if (string.IsNullOrWhiteSpace(serviceType))
+            throw new ValidationException("서비스 유형을 입력하세요.");
+
+        var contract = new Contract
+        {
+            ClientId = clientId,
+            ContractNumber = contractNumber.Trim(),
+            ServiceType = serviceType.Trim(),
+            ContractDate = DateTime.Today,
+            StartDate = startDate,
+            MonthlyFee = monthlyFee,
+            TotalAmount = totalAmount,
+            Status = "active",
+            PaymentStatus = "pending",
+            CreatedAt = DateTime.UtcNow,
+            UpdatedAt = DateTime.UtcNow
+        };
+
+        return await repository.CreateAsync(contract, ct);
+    }
+
+    public async Task<Contract?> GetByIdAsync(int id, CancellationToken ct = default) =>
+        await repository.GetByIdAsync(id, ct);
+
+    public async Task<IEnumerable<Contract>> GetAllAsync(CancellationToken ct = default) =>
+        await repository.GetAllAsync(ct);
+
+    public async Task<IEnumerable<Contract>> GetByClientIdAsync(int clientId, CancellationToken ct = default) =>
+        await repository.GetByClientIdAsync(clientId, ct);
+
+    public async Task<IEnumerable<Contract>> GetActiveContractsAsync(CancellationToken ct = default) =>
+        await repository.GetActiveContractsAsync(ct);
+
+    public async Task<IEnumerable<Contract>> GetExpiringContractsAsync(int daysAhead = 30, CancellationToken ct = default) =>
+        await repository.GetExpiringContractsAsync(daysAhead, ct);
+
+    public async Task<decimal> GetMonthlyRecurringRevenueAsync(CancellationToken ct = default) =>
+        await repository.GetMonthlyRecurringRevenueAsync(ct);
+}

src/TaxBaik.Application/Services/FaqService.cs

@@ -0,0 +1,42 @@
+namespace TaxBaik.Application.Services;
+
+using TaxBaik.Domain.Entities;
+using TaxBaik.Domain.Interfaces;
+
+public class FaqService(IFaqRepository repository)
+{
+    public static readonly string[] Categories =
+        ["기장세금신고", "부동산", "증여상속", "기타"];
+
+    public async Task<IEnumerable<Faq>> GetActiveAsync(CancellationToken ct = default) =>
+        await repository.GetActiveAsync(ct);
+
+    public async Task<IEnumerable<Faq>> GetAllAsync(CancellationToken ct = default) =>
+        await repository.GetAllAsync(ct);
+
+    public async Task<Faq?> GetByIdAsync(int id, CancellationToken ct = default) =>
+        await repository.GetByIdAsync(id, ct);
+
+    public async Task<int> CreateAsync(Faq faq, CancellationToken ct = default)
+    {
+        Validate(faq);
+        return await repository.CreateAsync(faq, ct);
+    }
+
+    public async Task UpdateAsync(Faq faq, CancellationToken ct = default)
+    {
+        Validate(faq);
+        await repository.UpdateAsync(faq, ct);
+    }
+
+    public async Task DeleteAsync(int id, CancellationToken ct = default) =>
+        await repository.DeleteAsync(id, ct);
+
+    private static void Validate(Faq faq)
+    {
+        if (string.IsNullOrWhiteSpace(faq.Question))
+            throw new ValidationException("질문을 입력하세요.");
+        if (string.IsNullOrWhiteSpace(faq.Answer))
+            throw new ValidationException("답변을 입력하세요.");
+    }
+}

src/TaxBaik.Application/Services/IInquiryNotificationService.cs

@@ -0,0 +1,7 @@
+namespace TaxBaik.Application.Services;
+
+public interface IInquiryNotificationService
+{
+    Task NotifyCreatedAsync(int inquiryId, string name, string phone, string serviceType, string message, string? ipAddress, DateTime createdAtUtc, CancellationToken ct = default);
+    Task NotifyStatusChangedAsync(int inquiryId, string name, string phone, string serviceType, string previousStatus, string newStatus, string? changedBy = null, CancellationToken ct = default);
+}

src/TaxBaik.Application/Services/InquiryService.cs

@@ -0,0 +1,152 @@
+namespace TaxBaik.Application.Services;
+
+using System.Text.RegularExpressions;
+using Microsoft.Extensions.Caching.Memory;
+using TaxBaik.Application.DTOs;
+using TaxBaik.Domain.Entities;
+using TaxBaik.Domain.Enums;
+using TaxBaik.Domain.Interfaces;
+
+public class InquiryService(
+    IInquiryRepository repository,
+    IInquiryNotificationService notificationService,
+    IMemoryCache memoryCache)
+{
+    private static readonly Regex PhoneRegex = new(@"^01[0-9]-\d{3,4}-\d{4}$");
+
+    public async Task<int> SubmitAsync(
+        string name, string phone, string serviceType, string message,
+        string? email = null, string? ipAddress = null, bool suppressNotification = false, CancellationToken ct = default)
+    {
+        if (string.IsNullOrWhiteSpace(name))
+            throw new ValidationException("이름을 입력하세요.");
+
+        if (!PhoneRegex.IsMatch(phone))
+            throw new ValidationException("올바른 전화번호를 입력하세요. (예: 010-1234-5678)");
+
+        if (string.IsNullOrWhiteSpace(message))
+            throw new ValidationException("문의 내용을 입력하세요.");
+
+        var inquiry = new Inquiry
+        {
+            Name = name.Trim(),
+            Phone = phone.Trim(),
+            Email = string.IsNullOrWhiteSpace(email) ? null : email.Trim(),
+            ServiceType = serviceType ?? "기타",
+            Message = message.Trim(),
+            IpAddress = ipAddress,
+            Status = InquiryStatusMapper.ToStorageValue(InquiryStatus.New),
+            CreatedAt = DateTime.UtcNow
+        };
+
+        var inquiryId = await repository.CreateAsync(inquiry, ct);
+        if (!suppressNotification)
+        {
+            await notificationService.NotifyCreatedAsync(inquiryId, inquiry.Name, inquiry.Phone, inquiry.ServiceType, inquiry.Message, inquiry.IpAddress, inquiry.CreatedAt, ct);
+        }
+        memoryCache.Remove(AdminDashboardService.CacheKey);
+        return inquiryId;
+    }
+
+    public async Task<Inquiry?> GetByIdAsync(int id, CancellationToken ct = default) =>
+        await repository.GetByIdAsync(id, ct);
+
+    public async Task<(IEnumerable<Inquiry>, int)> GetPagedAsync(
+        int page, int pageSize, string? status = null, CancellationToken ct = default) =>
+        await repository.GetPagedAsync(NormalizePage(page), NormalizePageSize(pageSize), NormalizeOptionalStatus(status), ct);
+
+    public Task<int> CountAsync(CancellationToken ct = default)
+        => repository.CountAsync(ct);
+
+    public Task<int> CountThisMonthAsync(CancellationToken ct = default)
+        => repository.CountThisMonthAsync(ct);
+
+    public Task<int> CountByStatusAsync(string status, CancellationToken ct = default)
+        => repository.CountByStatusAsync(status, ct);
+
+    public Task<int> CountByDateRangeAsync(DateTime startDate, DateTime endDate, CancellationToken ct = default)
+        => repository.CountByDateRangeAsync(startDate, endDate, ct);
+
+    public Task<int> CountByStatusAndDateAsync(string status, DateTime startDate, DateTime endDate, CancellationToken ct = default)
+        => repository.CountByStatusAndDateAsync(status, startDate, endDate, ct);
+
+    public async Task UpdateAdminMemoAsync(int id, string? adminMemo, CancellationToken ct = default) =>
+        await repository.UpdateAdminMemoAsync(id, adminMemo, ct);
+
+    public async Task<Inquiry?> UpdateAsync(int id, UpdateInquiryDto dto, CancellationToken ct = default)
+    {
+        var inquiry = await repository.GetByIdAsync(id, ct);
+        if (inquiry == null)
+            return null;
+
+        if (string.IsNullOrWhiteSpace(dto.Name))
+            throw new ValidationException("이름을 입력하세요.");
+
+        if (!PhoneRegex.IsMatch(dto.Phone))
+            throw new ValidationException("올바른 전화번호를 입력하세요. (예: 010-1234-5678)");
+
+        if (string.IsNullOrWhiteSpace(dto.Message))
+            throw new ValidationException("문의 내용을 입력하세요.");
+
+        if (!InquiryStatusMapper.TryParse(dto.Status, out var parsedStatus))
+            throw new ValidationException("지원하지 않는 문의 상태입니다.");
+
+        inquiry.Name = dto.Name.Trim();
+        inquiry.Phone = dto.Phone.Trim();
+        inquiry.Email = string.IsNullOrWhiteSpace(dto.Email) ? null : dto.Email.Trim();
+        inquiry.ServiceType = string.IsNullOrWhiteSpace(dto.ServiceType) ? "기타" : dto.ServiceType.Trim();
+        inquiry.Message = dto.Message.Trim();
+        inquiry.Status = InquiryStatusMapper.ToStorageValue(parsedStatus);
+        inquiry.AdminMemo = dto.AdminMemo;
+
+        await repository.UpdateAsync(inquiry, ct);
+        memoryCache.Remove(AdminDashboardService.CacheKey);
+        return inquiry;
+    }
+
+    public async Task LinkClientAsync(int inquiryId, int clientId, CancellationToken ct = default) =>
+        await repository.LinkClientAsync(inquiryId, clientId, ct);
+
+    public async Task UpdateStatusAsync(int id, string status, string? changedBy = null, CancellationToken ct = default)
+    {
+        if (!InquiryStatusMapper.TryParse(status, out var parsed))
+            throw new ValidationException("지원하지 않는 문의 상태입니다.");
+
+        var inquiry = await repository.GetByIdAsync(id, ct);
+        if (inquiry == null)
+            return;
+
+        var previousStatus = inquiry.Status;
+        var newStatus = InquiryStatusMapper.ToStorageValue(parsed);
+
+        await repository.UpdateStatusAsync(id, newStatus, ct);
+        await notificationService.NotifyStatusChangedAsync(id, inquiry.Name, inquiry.Phone, inquiry.ServiceType, previousStatus, newStatus, changedBy, ct);
+        memoryCache.Remove(AdminDashboardService.CacheKey);
+    }
+
+    public async Task DeleteAsync(int id, CancellationToken ct = default)
+    {
+        await repository.DeleteAsync(id, ct);
+        memoryCache.Remove(AdminDashboardService.CacheKey);
+    }
+
+    private static int NormalizePage(int page) => Math.Max(1, page);
+
+    private static int NormalizePageSize(int pageSize) => Math.Clamp(pageSize, 1, 100);
+
+    private static string? NormalizeOptionalStatus(string? status)
+    {
+        if (string.IsNullOrWhiteSpace(status))
+            return null;
+
+        if (!InquiryStatusMapper.TryParse(status, out var parsed))
+            throw new ValidationException("지원하지 않는 문의 상태입니다.");
+
+        return InquiryStatusMapper.ToStorageValue(parsed);
+    }
+}
+
+public class ValidationException : Exception
+{
+    public ValidationException(string message) : base(message) { }
+}

src/TaxBaik.Application/Services/InquiryStatusMapper.cs

@@ -0,0 +1,40 @@
+namespace TaxBaik.Application.Services;
+
+using TaxBaik.Domain.Enums;
+
+public static class InquiryStatusMapper
+{
+    public static readonly Dictionary<string, string> Labels = new()
+    {
+        ["new"]        = "신규",
+        ["consulting"] = "상담중",
+        ["contracted"] = "계약완료",
+        ["rejected"]   = "거절",
+        ["closed"]     = "종결",
+    };
+
+    public static string ToStorageValue(InquiryStatus status) => status switch
+    {
+        InquiryStatus.New        => "new",
+        InquiryStatus.Consulting => "consulting",
+        InquiryStatus.Contracted => "contracted",
+        InquiryStatus.Rejected   => "rejected",
+        InquiryStatus.Closed     => "closed",
+        _ => throw new ArgumentOutOfRangeException(nameof(status), status, null)
+    };
+
+    public static bool TryParse(string? value, out InquiryStatus status)
+    {
+        var key = value?.Trim().ToLowerInvariant();
+        status = key switch
+        {
+            "new"        => InquiryStatus.New,
+            "consulting" => InquiryStatus.Consulting,
+            "contracted" => InquiryStatus.Contracted,
+            "rejected"   => InquiryStatus.Rejected,
+            "closed"     => InquiryStatus.Closed,
+            _ => default
+        };
+        return key is "new" or "consulting" or "contracted" or "rejected" or "closed";
+    }
+}

src/TaxBaik.Application/Services/NoopInquiryNotificationService.cs

@@ -0,0 +1,10 @@
+namespace TaxBaik.Application.Services;
+
+public sealed class NoopInquiryNotificationService : IInquiryNotificationService
+{
+    public Task NotifyCreatedAsync(int inquiryId, string name, string phone, string serviceType, string message, string? ipAddress, DateTime createdAtUtc, CancellationToken ct = default)
+        => Task.CompletedTask;
+
+    public Task NotifyStatusChangedAsync(int inquiryId, string name, string phone, string serviceType, string previousStatus, string newStatus, string? changedBy = null, CancellationToken ct = default)
+        => Task.CompletedTask;
+}

src/TaxBaik.Application/Services/PortalUserService.cs

@@ -0,0 +1,59 @@
+namespace TaxBaik.Application.Services;
+
+using TaxBaik.Domain.Entities;
+using TaxBaik.Domain.Interfaces;
+
+public class PortalUserService(IPortalUserRepository repository)
+{
+    public async Task<PortalUser?> GetByEmailAsync(string email, CancellationToken ct = default) =>
+        await repository.GetByEmailAsync(email.Trim(), ct);
+
+    public async Task<PortalUser?> GetByProviderAsync(string provider, string providerId, CancellationToken ct = default) =>
+        await repository.GetByProviderAsync(provider.Trim(), providerId.Trim(), ct);
+
+    public async Task<int> RegisterLocalAsync(string name, string email, string phone, string? passwordHash, int? clientId = null, CancellationToken ct = default) =>
+        await RegisterAsync(name, email, phone, "local", null, passwordHash, clientId, ct);
+
+    public async Task<int> RegisterOAuthAsync(string name, string email, string? phone, string provider, string providerId, int? clientId = null, CancellationToken ct = default) =>
+        await RegisterAsync(name, email, phone, provider, providerId, null, clientId, ct);
+
+    public async Task LinkOAuthAsync(PortalUser user, string provider, string providerId, string? displayName = null, string? email = null, CancellationToken ct = default)
+    {
+        user.Name = string.IsNullOrWhiteSpace(displayName) ? user.Name : displayName.Trim();
+        user.Email = string.IsNullOrWhiteSpace(email) ? user.Email : email.Trim();
+        if (string.IsNullOrWhiteSpace(user.PasswordHash))
+        {
+            user.Provider = provider.Trim();
+            user.ProviderId = providerId.Trim();
+        }
+        await repository.UpdateAsync(user, ct);
+    }
+
+    public async Task AttachClientAsync(PortalUser user, int clientId, CancellationToken ct = default)
+    {
+        user.ClientId = clientId;
+        await repository.UpdateAsync(user, ct);
+    }
+
+    private async Task<int> RegisterAsync(string name, string email, string? phone, string provider, string? providerId, string? passwordHash, int? clientId, CancellationToken ct)
+    {
+        if (string.IsNullOrWhiteSpace(name))
+            throw new ValidationException("이름을 입력하세요.");
+        if (string.IsNullOrWhiteSpace(email))
+            throw new ValidationException("이메일을 입력하세요.");
+
+        var user = new PortalUser
+        {
+            ClientId = clientId,
+            Name = name.Trim(),
+            Email = email.Trim(),
+            Phone = string.IsNullOrWhiteSpace(phone) ? null : phone.Trim(),
+            Provider = provider,
+            ProviderId = providerId,
+            PasswordHash = passwordHash,
+            CreatedAt = DateTime.UtcNow
+        };
+
+        return await repository.CreateAsync(user, ct);
+    }
+}

src/TaxBaik.Application/Services/RevenueTrackingService.cs

@@ -0,0 +1,55 @@
+namespace TaxBaik.Application.Services;
+
+using TaxBaik.Domain.Entities;
+using TaxBaik.Domain.Interfaces;
+
+public class RevenueTrackingService(IRevenueTrackingRepository repository)
+{
+    public async Task<int> CreateAsync(int clientId, string invoiceNumber, DateTime invoiceDate,
+        decimal amount, string? serviceType = null, DateTime? dueDate = null, CancellationToken ct = default)
+    {
+        if (clientId <= 0)
+            throw new ValidationException("유효한 고객을 선택하세요.");
+        if (string.IsNullOrWhiteSpace(invoiceNumber))
+            throw new ValidationException("인보이스 번호를 입력하세요.");
+        if (amount <= 0)
+            throw new ValidationException("금액은 0보다 커야 합니다.");
+
+        var revenue = new RevenueTracking
+        {
+            ClientId = clientId,
+            InvoiceNumber = invoiceNumber.Trim(),
+            InvoiceDate = invoiceDate,
+            Amount = amount,
+            ServiceType = string.IsNullOrWhiteSpace(serviceType) ? null : serviceType.Trim(),
+            DueDate = dueDate,
+            PaymentStatus = "pending",
+            CreatedAt = DateTime.UtcNow,
+            UpdatedAt = DateTime.UtcNow
+        };
+
+        return await repository.CreateAsync(revenue, ct);
+    }
+
+    public async Task<IEnumerable<RevenueTracking>> GetByClientIdAsync(int clientId, CancellationToken ct = default) =>
+        await repository.GetByClientIdAsync(clientId, ct);
+
+    public async Task<IEnumerable<RevenueTracking>> GetAllAsync(CancellationToken ct = default) =>
+        await repository.GetAllAsync(ct);
+
+    public async Task<IEnumerable<RevenueTracking>> GetPendingPaymentsAsync(CancellationToken ct = default) =>
+        await repository.GetPendingPaymentsAsync(ct);
+
+    public async Task<IEnumerable<RevenueTracking>> GetMonthlyRevenueAsync(DateTime month, CancellationToken ct = default)
+    {
+        var startDate = new DateTime(month.Year, month.Month, 1);
+        var endDate = startDate.AddMonths(1).AddDays(-1);
+        return await repository.GetByDateRangeAsync(startDate, endDate, ct);
+    }
+
+    public async Task MarkPaidAsync(int id, DateTime paymentDate, CancellationToken ct = default) =>
+        await repository.MarkPaidAsync(id, paymentDate, ct);
+
+    public async Task<decimal> GetTotalRevenueAsync(DateTime startDate, DateTime endDate, CancellationToken ct = default) =>
+        await repository.GetTotalRevenueAsync(startDate, endDate, ct);
+}

src/TaxBaik.Application/Services/SeasonalMarketingService.cs

@@ -0,0 +1,40 @@
+namespace TaxBaik.Application.Services;
+
+using TaxBaik.Application.Seasonal;
+
+public class SeasonalMarketingService
+{
+    public CurrentSeasonDto? GetCurrentSeason()
+    {
+        var today = DateTime.Today;
+
+        foreach (var season in TaxSeasonCalendar.Seasons)
+        {
+            var start = new DateTime(today.Year, season.StartMonth, season.StartDay);
+            var end = new DateTime(today.Year, season.EndMonth, season.EndDay);
+
+            if (today >= start && today <= end)
+            {
+                var effectiveEnd = BusinessDayCalculator.GetEffectiveBusinessDate(DateOnly.FromDateTime(end)).ToDateTime(TimeOnly.MinValue);
+                var days = BusinessDayCalculator.GetBusinessDayDiff(DateOnly.FromDateTime(end), DateOnly.FromDateTime(today));
+                return new CurrentSeasonDto
+                {
+                    Key = season.Key,
+                    Name = season.Name,
+                    HeroHeadline = season.HeroHeadline,
+                    HeroSubtext = season.HeroSubtext,
+                    UrgencyBadge = season.UrgencyBadge.Replace("{n}", days.ToString()),
+                    FocusService = season.FocusService,
+                    RelatedCategorySlug = season.RelatedCategorySlug,
+                    CtaText = season.CtaText,
+                    DaysUntilDeadline = days,
+                    Deadline = effectiveEnd
+                };
+            }
+        }
+
+        return null;
+    }
+
+    public IReadOnlyList<TaxSeason> GetFullCalendar() => TaxSeasonCalendar.Seasons;
+}

src/TaxBaik.Application/Services/SiteSettingService.cs

@@ -0,0 +1,23 @@
+using TaxBaik.Domain.Entities;
+using TaxBaik.Domain.Interfaces;
+
+namespace TaxBaik.Application.Services;
+
+public class SiteSettingService(ISiteSettingRepository repository)
+{
+    public Task<IReadOnlyDictionary<string, string>> GetAllAsync(CancellationToken ct = default)
+        => repository.GetAllAsync(ct);
+
+    public Task SaveAsync(string phone, string email, string kakaoUrl, string instagramUrl, CancellationToken ct = default)
+    {
+        var settings = new[]
+        {
+            new SiteSetting { Key = "PhoneNumber", Value = phone.Trim(), UpdatedAt = DateTime.UtcNow },
+            new SiteSetting { Key = "EmailAddress", Value = email.Trim(), UpdatedAt = DateTime.UtcNow },
+            new SiteSetting { Key = "KakaoChannelUrl", Value = kakaoUrl.Trim(), UpdatedAt = DateTime.UtcNow },
+            new SiteSetting { Key = "InstagramUrl", Value = instagramUrl.Trim(), UpdatedAt = DateTime.UtcNow },
+        };
+
+        return repository.UpsertAsync(settings, ct);
+    }
+}

src/TaxBaik.Application/Services/TaxFilingScheduleService.cs

@@ -0,0 +1,53 @@
+namespace TaxBaik.Application.Services;
+
+using TaxBaik.Domain.Entities;
+using TaxBaik.Domain.Interfaces;
+
+public class TaxFilingScheduleService(ITaxFilingScheduleRepository repository)
+{
+    public async Task<int> CreateAsync(int clientId, string filingType, DateTime dueDate, int filingYear,
+        int? assignedToId = null, CancellationToken ct = default)
+    {
+        if (clientId <= 0)
+            throw new ValidationException("유효한 고객을 선택하세요.");
+        if (string.IsNullOrWhiteSpace(filingType))
+            throw new ValidationException("신고 유형을 입력하세요.");
+        if (dueDate < DateTime.Today)
+            throw new ValidationException("마감일은 오늘 이후여야 합니다.");
+
+        var schedule = new TaxFilingSchedule
+        {
+            ClientId = clientId,
+            FilingType = filingType.Trim(),
+            DueDate = dueDate,
+            FilingYear = filingYear,
+            Status = "pending",
+            AssignedToId = assignedToId,
+            CreatedAt = DateTime.UtcNow,
+            UpdatedAt = DateTime.UtcNow
+        };
+
+        return await repository.CreateAsync(schedule, ct);
+    }
+
+    public async Task<TaxFilingSchedule?> GetByIdAsync(int id, CancellationToken ct = default) =>
+        await repository.GetByIdAsync(id, ct);
+
+    public async Task<IEnumerable<TaxFilingSchedule>> GetAllAsync(CancellationToken ct = default) =>
+        await repository.GetAllAsync(ct);
+
+    public async Task<IEnumerable<TaxFilingSchedule>> GetByClientIdAsync(int clientId, CancellationToken ct = default) =>
+        await repository.GetByClientIdAsync(clientId, ct);
+
+    public async Task<IEnumerable<TaxFilingSchedule>> GetUpcomingDuesAsync(int daysAhead = 30, CancellationToken ct = default) =>
+        await repository.GetUpcomingDuesAsync(daysAhead, ct);
+
+    public async Task MarkCompletedAsync(int id, CancellationToken ct = default) =>
+        await repository.MarkCompletedAsync(id, ct);
+
+    public async Task<int> GetPendingCountAsync(CancellationToken ct = default)
+    {
+        var pending = await repository.GetByStatusAsync("pending", ct);
+        return pending.Count();
+    }
+}

src/TaxBaik.Application/Services/TaxFilingService.cs

@@ -0,0 +1,47 @@
+namespace TaxBaik.Application.Services;
+
+using TaxBaik.Domain.Entities;
+using TaxBaik.Domain.Interfaces;
+
+public class TaxFilingService(ITaxFilingRepository repository)
+{
+    public static readonly string[] Statuses =
+        ["pending", "filed", "overdue"];
+
+    public static readonly Dictionary<string, string> StatusLabels = new()
+    {
+        ["pending"]  = "신고 예정",
+        ["filed"]    = "신고 완료",
+        ["overdue"]  = "기한 초과",
+    };
+
+    public async Task<IEnumerable<TaxFiling>> GetByClientIdAsync(int clientId, CancellationToken ct = default) =>
+        await repository.GetByClientIdAsync(clientId, ct);
+
+    public async Task<IEnumerable<TaxFiling>> GetUpcomingAsync(int daysAhead = 30, CancellationToken ct = default) =>
+        await repository.GetUpcomingAsync(daysAhead, ct);
+
+    public async Task<TaxFiling?> GetByIdAsync(int id, CancellationToken ct = default) =>
+        await repository.GetByIdAsync(id, ct);
+
+    public async Task<int> CreateAsync(TaxFiling filing, CancellationToken ct = default)
+    {
+        if (string.IsNullOrWhiteSpace(filing.FilingType))
+            throw new ValidationException("신고 유형을 선택하세요.");
+        if (filing.ClientId <= 0)
+            throw new ValidationException("고객을 선택하세요.");
+        if (filing.DueDate == default)
+            throw new ValidationException("신고 기한을 입력하세요.");
+        return await repository.CreateAsync(filing, ct);
+    }
+
+    public async Task UpdateAsync(TaxFiling filing, CancellationToken ct = default)
+    {
+        if (string.IsNullOrWhiteSpace(filing.FilingType))
+            throw new ValidationException("신고 유형을 선택하세요.");
+        await repository.UpdateAsync(filing, ct);
+    }
+
+    public async Task DeleteAsync(int id, CancellationToken ct = default) =>
+        await repository.DeleteAsync(id, ct);
+}

src/TaxBaik.Application/Services/TaxProfileService.cs

@@ -0,0 +1,64 @@
+namespace TaxBaik.Application.Services;
+
+using TaxBaik.Domain.Entities;
+using TaxBaik.Domain.Interfaces;
+
+public class TaxProfileService(ITaxProfileRepository repository)
+{
+    public async Task<int> CreateAsync(int clientId, string? businessType, string? businessRegistration = null,
+        string? accountingMethod = null, DateTime? establishmentDate = null, CancellationToken ct = default)
+    {
+        if (clientId <= 0)
+            throw new ValidationException("유효한 고객을 선택하세요.");
+        if (string.IsNullOrWhiteSpace(businessType))
+            throw new ValidationException("사업 유형을 입력하세요.");
+
+        var profile = new TaxProfile
+        {
+            ClientId = clientId,
+            BusinessType = businessType.Trim(),
+            BusinessRegistration = string.IsNullOrWhiteSpace(businessRegistration) ? null : businessRegistration.Trim(),
+            EstablishmentDate = establishmentDate,
+            AccountingMethod = string.IsNullOrWhiteSpace(accountingMethod) ? null : accountingMethod.Trim(),
+            TaxRiskLevel = "normal",
+            CreatedAt = DateTime.UtcNow,
+            UpdatedAt = DateTime.UtcNow
+        };
+
+        return await repository.CreateAsync(profile, ct);
+    }
+
+    public async Task<TaxProfile?> GetByClientIdAsync(int clientId, CancellationToken ct = default) =>
+        await repository.GetByClientIdAsync(clientId, ct);
+
+    public async Task<IEnumerable<TaxProfile>> GetAllAsync(CancellationToken ct = default) =>
+        await repository.GetAllAsync(ct);
+
+    public async Task UpdateAsync(int profileId, string? businessType, string? accountingMethod,
+        DateTime? nextFilingDueDate, string taxRiskLevel = "normal", CancellationToken ct = default)
+    {
+        var profile = await repository.GetByIdAsync(profileId, ct);
+        if (profile == null)
+            throw new ValidationException("세무 프로필을 찾을 수 없습니다.");
+
+        if (!string.IsNullOrWhiteSpace(businessType))
+            profile.BusinessType = businessType.Trim();
+        if (!string.IsNullOrWhiteSpace(accountingMethod))
+            profile.AccountingMethod = accountingMethod.Trim();
+        profile.NextFilingDueDate = nextFilingDueDate;
+        profile.TaxRiskLevel = taxRiskLevel;
+        profile.UpdatedAt = DateTime.UtcNow;
+
+        await repository.UpdateAsync(profile, ct);
+    }
+
+    public async Task<IEnumerable<TaxProfile>> GetHighRiskProfilesAsync(CancellationToken ct = default) =>
+        await repository.GetByRiskLevelAsync("high", ct);
+
+    public async Task<IEnumerable<TaxProfile>> GetUpcomingFilingDuesAsync(int daysAhead = 30, CancellationToken ct = default)
+    {
+        var startDate = DateTime.Today;
+        var endDate = startDate.AddDays(daysAhead);
+        return await repository.GetUpcomingFilingDuesAsync(startDate, endDate, ct);
+    }
+}

src/TaxBaik.Application/Services/TelegramReportService.cs

@@ -0,0 +1,74 @@
+namespace TaxBaik.Application.Services;
+
+public record TelegramDailyReport(
+    DateOnly Date,
+    int NewInquiries,
+    int PendingInquiries,
+    int NewClients,
+    int PendingTaxFilings,
+    int PendingPayments);
+
+public record TelegramWeeklyReport(
+    DateOnly WeekStart,
+    DateOnly WeekEnd,
+    int NewInquiries,
+    int NewClients,
+    int UpcomingTaxFilings,
+    decimal RevenueThisWeek);
+
+public class TelegramReportService(
+    InquiryService inquiryService,
+    ClientService clientService,
+    TaxFilingScheduleService taxFilingScheduleService,
+    RevenueTrackingService revenueTrackingService)
+{
+    public async Task<TelegramDailyReport> BuildDailyReportAsync(DateOnly date, CancellationToken ct = default)
+    {
+        var start = date.ToDateTime(TimeOnly.MinValue, DateTimeKind.Utc);
+        var end = date.ToDateTime(TimeOnly.MaxValue, DateTimeKind.Utc);
+
+        return new TelegramDailyReport(
+            Date: date,
+            NewInquiries: await inquiryService.CountByDateRangeAsync(start, end, ct),
+            PendingInquiries: await inquiryService.CountByStatusAsync("new", ct),
+            NewClients: await clientService.CountCreatedAtRangeAsync(start, end, ct),
+            PendingTaxFilings: await taxFilingScheduleService.GetPendingCountAsync(ct),
+            PendingPayments: (await revenueTrackingService.GetPendingPaymentsAsync(ct)).Count());
+    }
+
+    public async Task<TelegramWeeklyReport> BuildWeeklyReportAsync(DateOnly weekStart, CancellationToken ct = default)
+    {
+        var weekEnd = weekStart.AddDays(6);
+        var start = weekStart.ToDateTime(TimeOnly.MinValue, DateTimeKind.Utc);
+        var end = weekEnd.ToDateTime(TimeOnly.MaxValue, DateTimeKind.Utc);
+        var upcomingEnd = weekEnd.AddDays(7).ToDateTime(TimeOnly.MaxValue, DateTimeKind.Utc);
+
+        var revenue = await revenueTrackingService.GetTotalRevenueAsync(start, end, ct);
+
+        return new TelegramWeeklyReport(
+            WeekStart: weekStart,
+            WeekEnd: weekEnd,
+            NewInquiries: await inquiryService.CountByDateRangeAsync(start, end, ct),
+            NewClients: await clientService.CountCreatedAtRangeAsync(start, end, ct),
+            UpcomingTaxFilings: (await taxFilingScheduleService.GetUpcomingDuesAsync(14, ct))
+                .Count(x => x.DueDate >= start && x.DueDate <= upcomingEnd),
+            RevenueThisWeek: revenue);
+    }
+
+    public static string FormatDailyMessage(TelegramDailyReport report) =>
+        $"<b>📊 일간 리포트</b>\n\n" +
+        $"기준일: <code>{report.Date:yyyy-MM-dd}</code>\n" +
+        $"신규 문의: <code>{report.NewInquiries}</code>\n" +
+        $"처리 대기 문의: <code>{report.PendingInquiries}</code>\n" +
+        $"신규 고객: <code>{report.NewClients}</code>\n" +
+        $"신고 대기: <code>{report.PendingTaxFilings}</code>\n" +
+        $"미수 청구: <code>{report.PendingPayments}</code>";
+
+    public static string FormatWeeklyMessage(TelegramWeeklyReport report) =>
+        $"<b>📈 주간 리포트</b>\n\n" +
+        $"기간: <code>{report.WeekStart:yyyy-MM-dd}</code> ~ <code>{report.WeekEnd:yyyy-MM-dd}</code>\n" +
+        $"신규 문의: <code>{report.NewInquiries}</code>\n" +
+        $"신규 고객: <code>{report.NewClients}</code>\n" +
+        $"다가오는 신고: <code>{report.UpcomingTaxFilings}</code>\n" +
+        $"주간 매출: <code>₩{report.RevenueThisWeek:N0}</code>";
+}

src/TaxBaik.Application/TaxBaik.Application.csproj

@@ -0,0 +1,16 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <ItemGroup>
+    <ProjectReference Include="..\TaxBaik.Domain\TaxBaik.Domain.csproj" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.Extensions.DependencyInjection.Abstractions" Version="8.0.0" />
+    <PackageReference Include="Microsoft.Extensions.Caching.Abstractions" Version="10.0.0" />
+  </ItemGroup>
+
+  <PropertyGroup>
+    <TargetFramework>net10.0</TargetFramework>
+    <Nullable>enable</Nullable>
+    <ImplicitUsings>enable</ImplicitUsings>
+  </PropertyGroup>
+</Project>

src/TaxBaik.Application/Utils/BusinessDayCalculator.cs

@@ -0,0 +1,75 @@
+namespace TaxBaik.Application.Utils;
+
+public static class BusinessDayCalculator
+{
+    private static readonly HashSet<DateOnly> HolidayDates = new()
+    {
+        // 2026
+        new DateOnly(2026, 1, 1),
+        new DateOnly(2026, 2, 16),
+        new DateOnly(2026, 2, 17),
+        new DateOnly(2026, 2, 18),
+        new DateOnly(2026, 3, 1),
+        new DateOnly(2026, 3, 2),
+        new DateOnly(2026, 5, 5),
+        new DateOnly(2026, 5, 25),
+        new DateOnly(2026, 6, 6),
+        new DateOnly(2026, 8, 15),
+        new DateOnly(2026, 8, 16),
+        new DateOnly(2026, 8, 17),
+        new DateOnly(2026, 9, 24),
+        new DateOnly(2026, 9, 25),
+        new DateOnly(2026, 9, 26),
+        new DateOnly(2026, 10, 3),
+        new DateOnly(2026, 10, 4),
+        new DateOnly(2026, 10, 5),
+        new DateOnly(2026, 10, 9),
+        new DateOnly(2026, 12, 25),
+
+        // 2027
+        new DateOnly(2027, 1, 1),
+        new DateOnly(2027, 2, 6),
+        new DateOnly(2027, 2, 7),
+        new DateOnly(2027, 2, 8),
+        new DateOnly(2027, 2, 9),
+        new DateOnly(2027, 3, 1),
+        new DateOnly(2027, 3, 2),
+        new DateOnly(2027, 5, 5),
+        new DateOnly(2027, 5, 13),
+        new DateOnly(2027, 6, 6),
+        new DateOnly(2027, 8, 15),
+        new DateOnly(2027, 8, 16),
+        new DateOnly(2027, 9, 14),
+        new DateOnly(2027, 9, 15),
+        new DateOnly(2027, 9, 16),
+        new DateOnly(2027, 10, 3),
+        new DateOnly(2027, 10, 4),
+        new DateOnly(2027, 10, 9),
+        new DateOnly(2027, 10, 10),
+        new DateOnly(2027, 10, 11),
+        new DateOnly(2027, 12, 25),
+        new DateOnly(2027, 12, 26)
+    };
+
+    public static DateOnly GetEffectiveDueDate(DateOnly dueDate)
+    {
+        var effectiveDate = dueDate;
+        while (!IsBusinessDay(effectiveDate))
+        {
+            effectiveDate = effectiveDate.AddDays(1);
+        }
+
+        return effectiveDate;
+    }
+
+    public static int GetDday(DateOnly dueDate, DateOnly? referenceDate = null)
+    {
+        var today = referenceDate ?? DateOnly.FromDateTime(DateTime.Today);
+        var effectiveDueDate = GetEffectiveDueDate(dueDate);
+        return effectiveDueDate.DayNumber - today.DayNumber;
+    }
+
+    public static bool IsBusinessDay(DateOnly date)
+        => date.DayOfWeek is not DayOfWeek.Saturday and not DayOfWeek.Sunday
+           && !HolidayDates.Contains(date);
+}

src/TaxBaik.Application/Utils/VersionInfo.cs

@@ -0,0 +1,7 @@
+namespace TaxBaik.Application.Utils;
+
+public class VersionInfo
+{
+    public string Version { get; set; } = "unknown";
+    public string Built { get; set; } = "unknown";
+}