🔧 chore: GameService 리팩토링

Author: silver-eunjoo

backend/src/main/java/io/f1/backend/domain/game/app/GameService.java

@@ -217,7 +217,7 @@ private void updateRank(Room room, GameResultListResponse gameResultListResponse
 
             Player player = room.getPlayerByUserId(playerId);
 
-            if (Objects.equals(player.getState(), ConnectionState.DISCONNECTED)) {
+            if (room.isPlayerInState(playerId, ConnectionState.DISCONNECTED)) {
                 statService.updateRank(playerId, false, 0);
                 continue;
             }