클라이언트 핑퐁 추가

@@ -73,6 +73,10 @@ const Room: React.FC = () => {
     }
   }, [roomData]);
 
+  const handlePing = useCallback(() => {
+    socket.emit('ping', {}, () => {});
+  }, []);
+
   useEffect(() => {
     socket.on('msg', handleUpdateRoomUser);
     
@@ -90,9 +94,11 @@ const Room: React.FC = () => {
 
     setRoomData(location.state.roomData);
     socket.on('msg', handleInGame);
+    socket.on('ping', handlePing);
 
     return () => {
       socket.off('msg', handleInGame);
+      socket.off('ping', handlePing);
 
       const rawMessage: RawMessage = {
         type: MessageType.ROOM_LEAVE,