* add metrics in log sync package
* udpate auto sync metrics
* Add metrics for completed file sync
* add more metrics for serial file sync
* adjust default timeout value for auto sync
* fix metrics rpc for Timer type
* add metrics for channel
* refactor channel metrics
* add timeout metrics for segment sync
* refactor channel receiver
* Change default concurrent sync threads
* enhance log level in sync store
* Add rwlock in sync store to avoid concurrency issue
* enhance serial sync state machine log level
* wrap Instant for debug purpose
* add timestamp for connecting peers state
* Select random peer to sync chunks
* return sync peers states instead of connected peers only
* Use tokio async RwLock for sync store