Phase 8a: Wire up Checkout page to Customer* RPCs

- Checkout.razor.cs: Rewrite ProcessPayment() to use
  CustomerPurchasePackageAsync instead of disabled dead code
  (old TransactionsContract + UserOrderContract flow removed)
- Callback URL now points to /profile/payment-callback
  (reuses existing verify page with CustomerVerifyPackagePurchase)
- Remove unused DI: UserOrderContract, TransactionContract
- Remove unused usings: Transactions, UserOrder, WellKnownTypes
- Profile/Index.razor.cs: Rename basePackage → selectedPackage,
  tempCallbackUrl → callbackUrl (cosmetic)
- Build: 0 errors

src/FrontOffice.Main/Pages/Checkout.razor.cs

@@ -1,10 +1,7 @@
 
 using CMSMicroservice.Protobuf.Protos.Package;
-using CMSMicroservice.Protobuf.Protos.Transactions;
 using CMSMicroservice.Protobuf.Protos.UserAddress;
-using CMSMicroservice.Protobuf.Protos.UserOrder;
 using FrontOffice.Main.Utilities;
-using Google.Protobuf.WellKnownTypes;
 using Microsoft.AspNetCore.Components;
 using MudBlazor;
 using Severity = MudBlazor.Severity;
@@ -15,8 +12,6 @@ public partial class Checkout
 {
     [Inject] private PackageContract.PackageContractClient PackageClient { get; set; } = default!;
     [Inject] private UserAddressContract.UserAddressContractClient UserAddressContract { get; set; } = default!;
-    [Inject] private UserOrderContract.UserOrderContractClient UserOrderContract { get; set; } = default!;
-    [Inject] private TransactionsContract.TransactionsContractClient TransactionContract { get; set; } = default!;
 
     [Parameter] public long? PackageId { get; set; }
 
@@ -173,9 +168,6 @@ public partial class Checkout
 
     private async Task ProcessPayment()
     {
-        Snackbar.Add("درگاه پرداخت متصل نیست! لطفا در زمان دیگری مجددا تلاش فرمایید!", Severity.Warning);
-        return;
-
         if (!CanProceedToPayment || _selectedPackage == null || _selectedAddress == null)
         {
             Snackbar.Add("لطفاً پکیج و آدرس را انتخاب کنید.", Severity.Warning);
@@ -186,33 +178,29 @@ public partial class Checkout
 
         try
         {
-            // Step 1: Create payment request
-            var paymentRequest = new CustomerPaymentRequestRequest
+            var callbackUrl = $"{Navigation.BaseUri}profile/payment-callback";
+
+            var response = await PackageClient.CustomerPurchasePackageAsync(new CustomerPurchasePackageRequest
             {
-                Amount = _finalPrice,
-                CallbackUrl = $"{Navigation.BaseUri}checkout/callback",
-                Description = $"خرید پکیج {_selectedPackage.Title}",
-                Currency = CurrencyEnum.Irt,
-                Type = TransactionTypeEnum.Real
-            };
-
-            var paymentResponse = await TransactionContract.CustomerPaymentRequestAsync(paymentRequest);
-
-            if (string.IsNullOrEmpty(paymentResponse.PaymentGWUrl))
-                Snackbar.Add("آدرس درگاه پرداخت دریافت نشد.", Severity.Error);
-
-            // Step 2: Create user order
-            var orderRequest = new CreateNewUserOrderRequest
-            {
-                Amount = _finalPrice,
                 PackageId = _selectedPackage.Id,
-                PaymentStatus = CMSMicroservice.Protobuf.Protos.PaymentStatus.Pending
-            };
+                CallbackUrl = callbackUrl,
+                PurchaseMethod = PurchaseMethodEnum.PurchaseMethodGateway
+            });
 
-            var orderResponse = await UserOrderContract.CreateNewUserOrderAsync(orderRequest);
+            if (!response.Success)
+            {
+                Snackbar.Add(response.Message ?? "خطا در آغاز فرآیند پرداخت", Severity.Error);
+                return;
+            }
 
-            // Step 3: Redirect to payment gateway
-            Navigation.NavigateTo(paymentResponse.PaymentGWUrl);
+            if (!string.IsNullOrEmpty(response.PaymentGatewayUrl))
+            {
+                Navigation.NavigateTo(response.PaymentGatewayUrl, forceLoad: true);
+            }
+            else
+            {
+                Snackbar.Add("خطا در دریافت آدرس درگاه پرداخت", Severity.Error);
+            }
         }
         catch (Exception ex)
         {

src/FrontOffice.Main/Pages/Profile/Index.razor.cs

@@ -413,23 +413,22 @@ public partial class Index
         
         try
         {
-            // Get available packages and pick the first (base) one
+            // Get available packages and pick the first one
             var packages = await PackageContract.GetCustomerPackagesAsync(new GetCustomerPackagesRequest());
-            var basePackage = packages?.Models?.FirstOrDefault();
-            if (basePackage == null)
+            var selectedPackage = packages?.Models?.FirstOrDefault();
+            if (selectedPackage == null)
             {
                 Snackbar.Add("پکیجی برای خرید یافت نشد", Severity.Error);
                 return;
             }
             
             // Call CMS to initiate purchase (UserId from JWT, PackageId explicit)
-            // First, get orderId — then embed in callback URL
-            var tempCallbackUrl = $"{Navigation.BaseUri}profile/payment-callback";
+            var callbackUrl = $"{Navigation.BaseUri}profile/payment-callback";
             
             var response = await PackageContract.CustomerPurchasePackageAsync(new CustomerPurchasePackageRequest
             {
-                PackageId = basePackage.Id,
-                CallbackUrl = tempCallbackUrl,
+                PackageId = selectedPackage.Id,
+                CallbackUrl = callbackUrl,
                 PurchaseMethod = PurchaseMethodEnum.PurchaseMethodGateway
             });