support circuit breaker and integrate it with a smart rawkv client

[zz-jason]

Is your feature request related to a problem? Please describe.

once the cluster is gone, we need to discover that issue, respond to errors to the users immediately.

Describe the solution you'd like

1. can discover that the TiKV cluster is gone, respond to errors to the users immediately.
2. can discover that the TiKV cluster is recovered, respond to users with correct results in a reasonable time

Describe alternatives you've considered

circuit breaker implemented in https://github.com/alibaba/Sentinel/ and https://github.com/Netflix/Hystrix/

Additional context

N/A