feat: add PaymentStatus to discount order proto + expire pending orders background service

- Added payment_status field to GetOrderByIdResponse and OrderSummaryDto in proto
- Proto version bumped to 0.0.179
- Added PaymentStatus mapping in DiscountOrderService gRPC responses
- Created ExpirePendingOrdersService: expires pending orders after 30 min, releases inventory
- Registered background service in ConfigureServices

src/CMSMicroservice.Protobuf/CMSMicroservice.Protobuf.csproj

@@ -3,7 +3,7 @@
     <TargetFramework>net9.0</TargetFramework>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
-    <Version>0.0.178</Version>
+    <Version>0.0.179</Version>
     <DebugType>None</DebugType>
     <DebugSymbols>False</DebugSymbols>
     <GeneratePackageOnBuild>False</GeneratePackageOnBuild>

src/CMSMicroservice.Protobuf/Protos/discountorder.proto

@@ -137,6 +137,7 @@ message GetOrderByIdResponse
     repeated OrderItemDto items = 14;
     google.protobuf.Timestamp created = 15;
     google.protobuf.Timestamp last_modified = 16;
+    PaymentStatus payment_status = 17;
 }
 
 message AddressInfo
@@ -191,6 +192,7 @@ message OrderSummaryDto
     google.protobuf.StringValue tracking_code = 8;
     int32 items_count = 9;
     google.protobuf.Timestamp created = 10;
+    PaymentStatus payment_status = 11;
 }
 
 // ===== Admin: Get All Discount Orders =====