feat: Add gRPC API Layer - Phase 6 Integration

Added Protobuf definitions and gRPC services for all CQ layers:

Protobuf Files (4):
- configuration.proto: 2 Commands + 3 Queries (5 RPCs)
- clubmembership.proto: 3 Commands + 3 Queries (6 RPCs)
- networkmembership.proto: 3 Commands + 3 Queries (6 RPCs)
- commission.proto: 5 Commands + 4 Queries (9 RPCs)

gRPC Services (4):
- ConfigurationService: SetConfigurationValue, Deactivate, GetByKey, GetAll, GetHistory
- ClubMembershipService: Activate, Deactivate, AssignFeature, Get, GetAll, GetHistory
- NetworkMembershipService: Join, Move, Remove, GetPosition, GetTree, GetHistory
- CommissionService: Calculate+Process+Withdraw (5 commands), Get queries (4)

Features:
- HTTP transcoding enabled via google.api.http annotations
- Auto-registration via ConfigureGrpcEndpoints
- MetaData pagination support
- Request/Response DTOs for all endpoints
- Integration with MediatR CQRS handlers

Total: 4 proto files, 4 service classes, 26 RPC endpoints
Build: ✅ Successful (0 errors)

src/CMSMicroservice.Protobuf/CMSMicroservice.Protobuf.csproj

@@ -43,6 +43,11 @@
     <Protobuf Include="Protos\category.proto" ProtoRoot="Protos\" GrpcServices="Both" />
     <Protobuf Include="Protos\tag.proto" ProtoRoot="Protos\" GrpcServices="Both" />
     <Protobuf Include="Protos\pruducttag.proto" ProtoRoot="Protos\" GrpcServices="Both" />
+    <!-- Network Club Commission System - Phase 6 -->
+    <Protobuf Include="Protos\configuration.proto" ProtoRoot="Protos\" GrpcServices="Both" />
+    <Protobuf Include="Protos\clubmembership.proto" ProtoRoot="Protos\" GrpcServices="Both" />
+    <Protobuf Include="Protos\networkmembership.proto" ProtoRoot="Protos\" GrpcServices="Both" />
+    <Protobuf Include="Protos\commission.proto" ProtoRoot="Protos\" GrpcServices="Both" />
   </ItemGroup>
 
   <Target Name="PushToFoursatNuget" AfterTargets="Pack">