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.Web.Client/Services/ClientBrowserClient.cs

@@ -0,0 +1,141 @@
+namespace TaxBaik.Web.Services;
+
+using System.Net.Http;
+using System.Net.Http.Json;
+using TaxBaik.Application.DTOs;
+using TaxBaik.Domain.Entities;
+
+/// <summary>
+/// Client API Client for Admin Blazor
+/// SOLID: Single Responsibility - Client API calls only
+/// </summary>
+public interface IClientBrowserClient
+{
+    Task<(IEnumerable<Client> Items, int Total)> GetPagedAsync(
+        int page = 1, int pageSize = 20, string? status = null, string? search = null, CancellationToken ct = default);
+    Task<Client?> GetByIdAsync(int id, CancellationToken ct = default);
+    Task<Client?> CreateAsync(CreateClientDto dto, CancellationToken ct = default);
+    Task<Client?> UpdateAsync(int id, CreateClientDto dto, CancellationToken ct = default);
+    Task<bool> DeleteAsync(int id, CancellationToken ct = default);
+}
+
+public class ClientBrowserClient : IClientBrowserClient
+{
+    private readonly HttpClient _http;
+    private readonly ILogger<ClientBrowserClient> _logger;
+    private readonly ITokenStore _tokenStore;
+
+    public ClientBrowserClient(HttpClient http, ILogger<ClientBrowserClient> logger, ITokenStore tokenStore)
+    {
+        _http = http;
+        _logger = logger;
+        _tokenStore = tokenStore;
+    }
+
+    private void EnsureAuthHeader()
+    {
+        if (!string.IsNullOrEmpty(_tokenStore.AccessToken))
+            _http.DefaultRequestHeaders.Authorization = new("Bearer", _tokenStore.AccessToken);
+        else
+            _http.DefaultRequestHeaders.Authorization = null;
+    }
+
+    public async Task<(IEnumerable<Client> Items, int Total)> GetPagedAsync(
+        int page = 1, int pageSize = 20, string? status = null, string? search = null, CancellationToken ct = default)
+    {
+        try
+        {
+            EnsureAuthHeader();
+            var query = $"client?page={page}&pageSize={pageSize}";
+            if (!string.IsNullOrEmpty(status))
+                query += $"&status={status}";
+            if (!string.IsNullOrEmpty(search))
+                query += $"&search={Uri.EscapeDataString(search)}";
+
+            var result = await _http.GetFromJsonAsync<ClientPagedResponse>(query, cancellationToken: ct);
+            return result != null ? (result.Data, result.Total) : ([], 0);
+        }
+        catch (HttpRequestException ex)
+        {
+            _logger.LogError(ex, "Failed to fetch clients");
+            throw;
+        }
+    }
+
+    public async Task<Client?> GetByIdAsync(int id, CancellationToken ct = default)
+    {
+        try
+        {
+            EnsureAuthHeader();
+            return await _http.GetFromJsonAsync<Client>($"client/{id}", cancellationToken: ct);
+        }
+        catch (HttpRequestException ex)
+        {
+            _logger.LogError(ex, "Failed to fetch client {ClientId}", id);
+            throw;
+        }
+    }
+
+    public async Task<Client?> CreateAsync(CreateClientDto dto, CancellationToken ct = default)
+    {
+        try
+        {
+            EnsureAuthHeader();
+            var response = await _http.PostAsJsonAsync("client", dto, cancellationToken: ct);
+            if (!response.IsSuccessStatusCode)
+                return null;
+
+            var content = await response.Content.ReadAsStringAsync(ct);
+            return System.Text.Json.JsonSerializer.Deserialize<Client>(
+                content,
+                new System.Text.Json.JsonSerializerOptions { PropertyNameCaseInsensitive = true });
+        }
+        catch (HttpRequestException ex)
+        {
+            _logger.LogError(ex, "Failed to create client");
+            throw;
+        }
+    }
+
+    public async Task<Client?> UpdateAsync(int id, CreateClientDto dto, CancellationToken ct = default)
+    {
+        try
+        {
+            EnsureAuthHeader();
+            var response = await _http.PutAsJsonAsync($"client/{id}", dto, cancellationToken: ct);
+            if (!response.IsSuccessStatusCode)
+                return null;
+
+            var content = await response.Content.ReadAsStringAsync(ct);
+            return System.Text.Json.JsonSerializer.Deserialize<Client>(
+                content,
+                new System.Text.Json.JsonSerializerOptions { PropertyNameCaseInsensitive = true });
+        }
+        catch (HttpRequestException ex)
+        {
+            _logger.LogError(ex, "Failed to update client {ClientId}", id);
+            throw;
+        }
+    }
+
+    public async Task<bool> DeleteAsync(int id, CancellationToken ct = default)
+    {
+        try
+        {
+            EnsureAuthHeader();
+            var response = await _http.DeleteAsync($"client/{id}", cancellationToken: ct);
+            return response.IsSuccessStatusCode;
+        }
+        catch (HttpRequestException ex)
+        {
+            _logger.LogError(ex, "Failed to delete client {ClientId}", id);
+            throw;
+        }
+    }
+
+    private class ClientPagedResponse
+    {
+        public List<Client> Data { get; set; } = [];
+        public int Total { get; set; }
+    }
+}