Migrate SiteSettings controller to FastEndpoints

Refactored SiteSettingsController to FastEndpoints pattern:
- Created GetEndpoint.cs: GET /api/sitesettings (authorized)
- Created SaveEndpoint.cs: PUT /api/sitesettings (authorized)
- Removed legacy SiteSettingsController.cs

Both endpoints use Bearer token authentication and are auto-discovered
by FastEndpoints configuration in Program.cs.

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

src/TaxBaik.Web/Endpoints/AdminDashboard/GetRecentInquiriesEndpoint.cs

@@ -0,0 +1,40 @@
+using FastEndpoints;
+using TaxBaik.Application.Services;
+
+namespace TaxBaik.Web.Endpoints.AdminDashboard;
+
+public class GetRecentInquiriesEndpoint : Endpoint<RecentInquiriesQuery, RecentInquiriesResponse>
+{
+    private readonly AdminDashboardService _dashboardService;
+
+    public GetRecentInquiriesEndpoint(AdminDashboardService dashboardService)
+    {
+        _dashboardService = dashboardService;
+    }
+
+    public override void Configure()
+    {
+        Get("/api/admin-dashboard/recent-inquiries");
+        Policies("Bearer");
+    }
+
+    public override async Task HandleAsync(RecentInquiriesQuery request, CancellationToken ct)
+    {
+        try
+        {
+            var limit = request.Limit <= 0 ? 10 : request.Limit;
+            if (limit > 100) limit = 100; // Security: max 100
+
+            var inquiries = await _dashboardService.GetRecentInquiriesAsync(limit, ct);
+            await SendAsync(new RecentInquiriesResponse
+            {
+                Data = inquiries.ToList(),
+                Limit = limit
+            }, 200, cancellation: ct);
+        }
+        catch (Exception ex)
+        {
+            await SendErrorsAsync(500, ct);
+        }
+    }
+}