feat: Phase 5 Browser Clients and deployment notification strategy

Phase 5: Tax & CRM Browser Clients
- 5 API client interfaces (TaxProfile, Filing, Activity, Contract, Revenue)
- Automatic token refresh for all clients
- Error logging with fallback empty lists
- Program.cs DI registration

Telegram Deployment Notifications:
- System chat (-5585148480): deployment success/failure
- Inquiry chat (-5434691215): customer inquiries
- Login alerts disabled (spam prevention)

Architecture:
Blazor -> BrowserClient (HttpClient+TokenRefresh) -> API -> Services -> DB

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

TaxBaik.Web/Program.cs

@@ -13,6 +13,7 @@ using TaxBaik.Application;
 using TaxBaik.Application.Services;
 using TaxBaik.Infrastructure;
 using TaxBaik.Web.Services;
+using TaxBaik.Web.Services.AdminClients;
 
 var builder = WebApplication.CreateBuilder(args);
 var isProduction = builder.Environment.IsProduction();
@@ -135,6 +136,42 @@ builder.Services.AddHttpClient<IAnnouncementBrowserClient, AnnouncementBrowserCl
 })
     .AddHttpMessageHandler<TokenRefreshHandler>();
 
+// Phase 5: Tax Accounting & CRM Browser Clients
+using (var scope = builder.Services.BuildServiceProvider().CreateScope())
+{
+    var logger = scope.ServiceProvider.GetRequiredService<ILogger<Program>>();
+
+    builder.Services.AddHttpClient<ITaxProfileBrowserClient, TaxProfileBrowserClient>(client =>
+    {
+        client.BaseAddress = new Uri(apiBaseUrl);
+    })
+        .AddHttpMessageHandler<TokenRefreshHandler>();
+
+    builder.Services.AddHttpClient<ITaxFilingScheduleBrowserClient, TaxFilingScheduleBrowserClient>(client =>
+    {
+        client.BaseAddress = new Uri(apiBaseUrl);
+    })
+        .AddHttpMessageHandler<TokenRefreshHandler>();
+
+    builder.Services.AddHttpClient<IConsultingActivityBrowserClient, ConsultingActivityBrowserClient>(client =>
+    {
+        client.BaseAddress = new Uri(apiBaseUrl);
+    })
+        .AddHttpMessageHandler<TokenRefreshHandler>();
+
+    builder.Services.AddHttpClient<IContractBrowserClient, ContractBrowserClient>(client =>
+    {
+        client.BaseAddress = new Uri(apiBaseUrl);
+    })
+        .AddHttpMessageHandler<TokenRefreshHandler>();
+
+    builder.Services.AddHttpClient<IRevenueTrackingBrowserClient, RevenueTrackingBrowserClient>(client =>
+    {
+        client.BaseAddress = new Uri(apiBaseUrl);
+    })
+        .AddHttpMessageHandler<TokenRefreshHandler>();
+}
+
 // UI & 캐시 (MudBlazor Theme Customization)
 builder.Services.AddMudServices(config =>
 {