fix(idiom): split display - winner sees in private, others in public

app/Http/Controllers/IdiomQuizController.php

@@ -197,7 +197,7 @@ class IdiomQuizController extends Controller
             $user->save();
         }
 
-        // 广播结果
+        // 广播结果（前端通过 IdiomGameAnswered 事件做分屏显示）
         broadcast(new IdiomGameAnswered(
             roomId: $roomId,
             roundId: $round->id,
@@ -207,7 +207,7 @@ class IdiomQuizController extends Controller
             rewardExp: $round->reward_exp,
         ));
 
-        // 推 MessageSent 系统通知
+        // 存聊天记录（不广播，避免重复显示）
         $resultMsg = [
             'id' => $this->chatState->nextMessageId($roomId),
             'room_id' => $roomId,
@@ -220,7 +220,6 @@ class IdiomQuizController extends Controller
             'sent_at' => now()->toDateTimeString(),
         ];
         $this->chatState->pushMessage($roomId, $resultMsg);
-        broadcast(new \App\Events\MessageSent($roomId, $resultMsg));
 
         \Illuminate\Support\Facades\Redis::del($lockKey);