feat(game): 支持玩家显示名称的多种数据源

- 在麻将游戏页面中添加本地缓存头像URL的优先级处理
- 为玩家座位信息添加自定义显示名称功能
- 支持从player_name或PlayerName字段获取玩家名称
- 实现当前用户显示名称的回退逻辑
- 更新API接口定义以支持可选的玩家名称字段

src/views/ChengduGamePage.vue

@@ -257,10 +257,11 @@ const seatDecor = computed<Record<SeatKey, SeatPlayerCardModel>>(() => {
     const avatarUrl = seat.isSelf
       ? (localCachedAvatarUrl.value || seat.player.avatarURL || '')
       : (seat.player.avatarURL || '')
+    const selfDisplayName = seat.player.displayName || loggedInUserName.value || '你自己'
 
     result[seat.key] = {
       avatarUrl,
-      name: seat.isSelf ? '你自己' : displayName,
+      name: seat.isSelf ? selfDisplayName : displayName,
       dealer: seat.player.seatIndex === dealerIndex,
       isTurn: seat.isTurn,
       missingSuitLabel: missingSuitLabel(seat.player.missingSuit),