健康检查

在brpc的客户端，如果每隔一段时间才调用，如每隔5分钟，有什么办法知道连接有异常了，客户端channal里面没有找到相应的通知接口。
难道只能由应用周期去检查，框架没有提供相应的能力？

Start with the brpc client Channel entry point and review how long-idle connections are currently represented. Check the existing client API and related issue discussion for any health or failure notification mechanism. Done means the expected behavior for detecting an abnormal connection and notifying or exposing it to the application is defined and documented.

Written by the indexing model from the issue text.