Fix namespace references in replication code

- Change StorageReplication to DatabaseReplication in sync_protocol.hpp
- Change StorageReplication to DatabaseReplication in sync_protocol.cpp
- Change StorageReplication to DatabaseReplication in database_grpc_impl.hpp

service/src/database_grpc_impl.hpp

@@ -231,7 +231,7 @@ private:
 /**
  * gRPC service implementation for Storage Replication.
  */
-class DatabaseReplicationGrpcImpl final : public pb::StorageReplication::Service {
+class DatabaseReplicationGrpcImpl final : public pb::DatabaseReplication::Service {
 public:
     DatabaseReplicationGrpcImpl(
         MemoryStore& store,

service/src/replication/sync_protocol.cpp

@@ -233,7 +233,7 @@ void SyncProtocol::connectToPeer(PeerConnection& peer) {
         );
 
         // Create stub
-        peer.stub = pb::StorageReplication::NewStub(peer.channel);
+        peer.stub = pb::DatabaseReplication::NewStub(peer.channel);
 
         // Try to get node state to verify connection
         grpc::ClientContext context;

service/src/replication/sync_protocol.hpp

@@ -31,7 +31,7 @@ public:
         std::string address;
         std::string nodeId;
         std::shared_ptr<grpc::Channel> channel;
-        std::unique_ptr<pb::StorageReplication::Stub> stub;
+        std::unique_ptr<pb::DatabaseReplication::Stub> stub;
         std::atomic<bool> connected{false};
         uint64_t lastWatermark = 0;
         std::vector<std::string> collections;  // Collections on peer