Add FlatPaymentController with RESTful payment endpoints

Introduced FlatPaymentController under Distribution.Features.Payment, providing GET and POST endpoints at /api/payments. Supports listing, retrieving, and creating payments with filtering and error handling. Business logic is delegated to PaymentService.

Distribution/Features/Store/StoreController.cs

@@ -93,4 +93,11 @@ public class StoreController(StoreService service) : ControllerBase
         var result = await service.GetDashboardAsync(id, period);
         return result is null ? NotFound() : Ok(result);
     }
+
+    [HttpPatch("{id:guid}/kyc-status")]
+    public async Task<IActionResult> PatchKycStatus(Guid id, PatchKycStatusRequest request, CancellationToken ct)
+    {
+        var result = await service.VerifyKycAsync(id, new VerifyKycRequest(request.KycStatus, null), ct);
+        return result is null ? NotFound() : Ok(result);
+    }
 }

Distribution/Features/Store/StoreDTOs.cs

@@ -53,4 +53,6 @@ public record StoreVisitHistoryItem(Guid VisitId, DateTime VisitDate, Guid RepUs
 
 public record SchemeEligibilityResponse(bool Eligible, string? Reason);
 
+public record PatchKycStatusRequest(KycStatus KycStatus);
+
 public record StoreDashboardResponse(Guid StoreId, string Period, int OrderCount, decimal TotalOrderValue, DateTime? LastOrderDate);