fix: auto-fix code issues (cron)

- 修复重复导入/字段
- 修复异常处理 (BaseException -> 具体异常类型)
- 修复PEP8格式问题
- 添加类型注解
- 修复tingwu_client.py缩进错误

backend/test_phase8_task8.py

@@ -521,7 +521,7 @@ class TestOpsManager:
                 self.manager.update_failover_status(event.id, "completed")
                 updated_event = self.manager.get_failover_event(event.id)
                 assert updated_event.status == "completed"
-                self.log(f"Failover completed")
+                self.log("Failover completed")
 
             # 获取故障转移事件列表
             events = self.manager.list_failover_events(self.tenant_id)