feat(api): /api/sessions 账号会话列表(好友+群,今日消息数+最近联系时间,全本地聚合)

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

yunke-server/app/api/schemas.py

@@ -3,7 +3,7 @@
 from __future__ import annotations
 
 import datetime as dt
-from typing import Any, Generic, TypeVar
+from typing import Any, Generic, Literal, TypeVar
 
 from pydantic import BaseModel, ConfigDict
 
@@ -325,3 +325,22 @@ class StaffChatStatsOut(BaseModel):
     end: int  # ms-epoch
     summary: StaffChatStatsSummary
     customers: list[StaffChatCustomerOut]
+
+
+class SessionOut(BaseModel):
+    """账号会话列表的一行(好友或群)。"""
+
+    type: Literal["friend", "group"]
+    talker_id: str | None = None
+    room_id: str | None = None
+    name: str | None = None
+    avatar: str | None = None
+    today_count: int
+    last_chat_time: int | None = None
+
+
+class SessionListOut(BaseModel):
+    owner_account_id: str
+    channel: str
+    today_start: int
+    sessions: list[SessionOut]