feat: ChargeDiscountWallet - callback endpoint, gRPC RPC & service implementation

- Add /api/wallet/verify-discount-charge callback endpoint in PaymentCallbackController
- Add InitiateDiscountCharge RPC + request/response messages in userwallet.proto
- Add InitiateDiscountCharge gRPC service override in UserWalletService
- Add ChargeDiscountWallet using import for handler resolution

src/CMSMicroservice.Protobuf/Protos/userwallet.proto

@@ -88,6 +88,15 @@ service UserWalletContract
             get: "/Customer/GetMagicWalletStatus"
         };
     };
+
+    // ============= Discount Wallet Methods =============
+
+    rpc InitiateDiscountCharge(InitiateDiscountChargeRequest) returns (InitiateDiscountChargeResponse){
+        option (google.api.http) = {
+            post: "/Customer/InitiateDiscountCharge"
+            body: "*"
+        };
+    };
 }
 message CreateNewUserWalletRequest
 {
@@ -242,3 +251,17 @@ message GetMagicWalletStatusResponse
     google.protobuf.Timestamp magic_activated_at = 7;
     int32 purchase_cycle_count = 8; // تعداد دورهای خرید پکیج (0 = هنوز هیچ دوری تکمیل نشده)
 }
+
+// ============= Discount Wallet Messages =============
+
+message InitiateDiscountChargeRequest
+{
+    int64 amount = 1; // مبلغ واریزی (ریال)
+}
+
+message InitiateDiscountChargeResponse
+{
+    bool is_success = 1;
+    string gateway_url = 2;
+    string error_message = 3;
+}

src/CMSMicroservice.WebApi/Controllers/PaymentCallbackController.cs

@@ -1,5 +1,6 @@
 using CMSMicroservice.Application.Common.Interfaces;
 using CMSMicroservice.Application.DiscountShopCQ.Commands.CompleteOrderPayment;
+using CMSMicroservice.Application.WalletCQ.Commands.VerifyDiscountWalletCharge;
 using CMSMicroservice.Application.WalletCQ.Commands.VerifyMagicWalletCharge;
 using MediatR;
 using Microsoft.AspNetCore.Authorization;
@@ -186,4 +187,63 @@ public class PaymentCallbackController : ControllerBase
             return Redirect($"{frontOfficeBaseUrl}/magic-wallet?payment=failed");
         }
     }
+
+    /// <summary>
+    /// Callback برای شارژ کیف‌پول تخفیفی — زرین‌پال بعد از پرداخت کاربر را اینجا برمی‌گرداند
+    /// </summary>
+    [HttpGet("/api/wallet/verify-discount-charge")]
+    public async Task<IActionResult> DiscountChargeCallback(
+        [FromQuery(Name = "Authority")] string? authority,
+        [FromQuery(Name = "Status")] string? status,
+        CancellationToken cancellationToken)
+    {
+        var frontOfficeBaseUrl = _configuration["FrontOfficeBaseUrl"] ?? "https://localhost:5268";
+
+        _logger.LogInformation(
+            "Discount charge callback received: Authority={Authority}, Status={Status}",
+            authority, status);
+
+        try
+        {
+            if (string.IsNullOrEmpty(authority))
+            {
+                _logger.LogError("Discount charge callback: Authority is missing");
+                return Redirect($"{frontOfficeBaseUrl}/profile/charge-discount-wallet?payment=error&reason=no-authority");
+            }
+
+            // پیدا کردن PaymentTransaction برای استخراج UserId و Amount
+            var paymentTx = await _context.PaymentTransactions
+                .FirstOrDefaultAsync(pt => pt.Authority == authority, cancellationToken);
+
+            if (paymentTx == null || !paymentTx.UserId.HasValue)
+            {
+                _logger.LogError("Discount charge callback: PaymentTransaction not found for Authority={Authority}", authority);
+                return Redirect($"{frontOfficeBaseUrl}/profile/charge-discount-wallet?payment=error&reason=tx-not-found");
+            }
+
+            if (!string.Equals(status, "OK", StringComparison.OrdinalIgnoreCase))
+            {
+                _logger.LogWarning("Discount charge cancelled by user. Authority={Authority}", authority);
+                return Redirect($"{frontOfficeBaseUrl}/profile/charge-discount-wallet?payment=cancelled");
+            }
+
+            var result = await _sender.Send(new VerifyDiscountWalletChargeCommand
+            {
+                UserId = paymentTx.UserId.Value,
+                Amount = paymentTx.Amount,
+                Authority = authority
+            }, cancellationToken);
+
+            _logger.LogInformation(
+                "Discount charge completed successfully. Authority={Authority}, UserId={UserId}",
+                authority, paymentTx.UserId.Value);
+
+            return Redirect($"{frontOfficeBaseUrl}/profile/charge-discount-wallet?payment=success");
+        }
+        catch (Exception ex)
+        {
+            _logger.LogError(ex, "Discount charge callback error. Authority={Authority}", authority);
+            return Redirect($"{frontOfficeBaseUrl}/profile/charge-discount-wallet?payment=failed");
+        }
+    }
 }

src/CMSMicroservice.WebApi/Services/UserWalletService.cs

@@ -4,6 +4,7 @@ using CMSMicroservice.Application.UserWalletCQ.Commands.CreateNewUserWallet;
 using CMSMicroservice.Application.UserWalletCQ.Commands.UpdateUserWallet;
 using CMSMicroservice.Application.UserWalletCQ.Commands.DeleteUserWallet;
 using CMSMicroservice.Application.WalletCQ.Commands.ChargeMagicWallet;
+using CMSMicroservice.Application.WalletCQ.Commands.ChargeDiscountWallet;
 using CMSMicroservice.Application.UserWalletCQ.Queries.GetUserWallet;
 using CMSMicroservice.Application.UserWalletCQ.Queries.GetAllUserWalletByFilter;
 using CMSMicroservice.Application.UserWalletCQ.Queries.GetCustomerWalletChangeLog;
@@ -170,6 +171,27 @@ public class UserWalletService : UserWalletContract.UserWalletContractBase
         };
     }
 
+    // ============= Discount Wallet Methods =============
+
+    public override async Task<InitiateDiscountChargeResponse> InitiateDiscountCharge(
+        InitiateDiscountChargeRequest request, ServerCallContext context)
+    {
+        var userId = GetCurrentUserId();
+
+        var result = await _sender.Send(new ChargeDiscountWalletCommand
+        {
+            UserId = userId,
+            Amount = request.Amount
+        }, context.CancellationToken);
+
+        return new InitiateDiscountChargeResponse
+        {
+            IsSuccess = result.IsSuccess,
+            GatewayUrl = result.GatewayUrl ?? "",
+            ErrorMessage = result.ErrorMessage ?? ""
+        };
+    }
+
     public override async Task<GetMagicWalletStatusResponse> GetMagicWalletStatus(
         Google.Protobuf.WellKnownTypes.Empty request, ServerCallContext context)
     {