feat: 集成飞书通知和机器人对话系统

- 新增通知系统 (notifications 表、服务、API)
- 新增飞书定时任务结果推送 (webhook + 应用消息)
- 新增飞书应用消息发送服务 (feishu_app_service)
- 新增飞书 WebSocket 长连接事件监听 (苹果应用)
- 新增飞书账号绑定/解绑 API
- 新增橙子飞书机器人 (独立 WS 连接，固定路由到橙子助手 Agent)
- 执行记录添加 schedule_id，用户添加飞书绑定字段

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/app/api/agent_schedules.py

@@ -32,6 +32,7 @@ class ScheduleCreate(BaseModel):
     cron_expression: str = Field(..., description="标准 5 位 cron，如 0 9 * * *")
     input_message: str = Field(..., description="每次触发时发给 Agent 的消息")
     timezone: str = "Asia/Shanghai"
+    webhook_url: Optional[str] = Field(None, description="飞书机器人 Webhook URL（可选）")
 
 
 class ScheduleUpdate(BaseModel):
@@ -40,6 +41,7 @@ class ScheduleUpdate(BaseModel):
     input_message: Optional[str] = None
     timezone: Optional[str] = None
     enabled: Optional[bool] = None
+    webhook_url: Optional[str] = None
 
 
 class ScheduleResponse(BaseModel):
@@ -50,6 +52,7 @@ class ScheduleResponse(BaseModel):
     input_message: str
     timezone: str
     enabled: bool
+    webhook_url: Optional[str] = None
     last_run_at: Optional[datetime] = None
     last_run_status: Optional[str] = None
     next_run_at: datetime
@@ -104,6 +107,7 @@ async def create_schedule(
         cron_expression=data.cron_expression,
         input_message=data.input_message,
         timezone=data.timezone or "Asia/Shanghai",
+        webhook_url=data.webhook_url,
         enabled=True,
         next_run_at=next_run,
         user_id=current_user.id,
@@ -146,6 +150,8 @@ async def update_schedule(
         schedule.timezone = data.timezone
     if data.enabled is not None:
         schedule.enabled = data.enabled
+    if data.webhook_url is not None:
+        schedule.webhook_url = data.webhook_url
 
     schedule.updated_at = datetime.utcnow()
     db.commit()