refactor(grpc): bind TCP listener before etcd registration to prevent connection issues

- Change tokio-stream dependency to include net feature for TcpListenerStream
- Move TCP listener binding before etcd registry initialization in main function
- Pass pre-bound TcpListener to gRPC server instead of just SocketAddr
- Update gRPC server to use serve_with_incoming with TcpListenerStream
- Prevent peers from attempting connections before gRPC server is ready
- Ensure proper error handling for TCP binding failures during startup

grpc/mod.rs

@@ -27,6 +27,7 @@ use crate::service::AppService;
 
 pub async fn start_grpc_server(
     addr: SocketAddr,
+    listener: tokio::net::TcpListener,
     service: AppService,
 ) -> Result<(), Box<dyn std::error::Error>> {
     let token_svc = auth::TokenGrpcService::new(service.internal_auth.clone());
@@ -60,7 +61,7 @@ pub async fn start_grpc_server(
         .add_service(VoiceServiceServer::new(cs.voice))
         .add_service(StageServiceServer::new(cs.stage))
         .add_service(ChannelAuditServiceServer::new(cs.channel_audit))
-        .serve(addr)
+        .serve_with_incoming(tokio_stream::wrappers::TcpListenerStream::new(listener))
         .await?;
 
     Ok(())