refactor: speaking_ended 이벤트 리스너 일단 제거

packages/frontend/src/hooks/useSpeakingControl.ts

@@ -8,18 +8,5 @@ export const useSpeakingControl = (currentSpeaker: string | null, userId: string
     if (!socket || currentSpeaker !== userId) return;
     socket.emit('end_speaking');
   };
-
-  useEffect(() => {
-    if (!socket) return;
-
-    socket.on('speaking_ended', () => {
-      console.log('발언 종료 처리됨');
-    });
-
-    return () => {
-      socket.off('speaking_ended');
-    };
-  }, [socket]);
-
   return { endSpeakingEarly };
 };