feat(api): sessions加is_del过滤+filehelper置顶标记,accounts加avatar(raw_json提取)

Co-Authored-By: Claude <noreply@anthropic.com>

yunke-server/app/api/schemas.py

@@ -112,6 +112,9 @@ class AccountOut(BaseModel):
     contacts_num: int | None = None
     group_num: int | None = None
     is_on_job: bool | None = None
+    # 头像 URL — 从 raw_json.headImageUrl 提取(WeChat 有该键;WA 无 -> None;
+    # 对齐云客员工聊天窗口左侧头像,2026-08-25),由路由显式赋值。
+    avatar: str | None = None
     raw_json: dict[str, Any] | None = None
 
 
@@ -408,6 +411,8 @@ class SessionOut(BaseModel):
     room_id: str | None = None
     name: str | None = None
     avatar: str | None = None
+    # filehelper 会话置顶标记(对齐云客置顶区,2026-08-25);其余好友/群恒 False
+    pinned: bool = False
     today_count: int
     last_chat_time: int | None = None