* feat: write duration calculation in countdown as
interface. add more inputs as function argument
* feat: ExpTimeoutDuration
* fix: three dots usage
* feat: refine exp duration
* feat: add exp timeout config and use it in countdown
* feat: remove const countdown
* feat: remove use of interface in countdown, use error
* fix: countdown reset timer problem
* fix: add default ExpTimeoutConfig for config
* clean up the pool old round
* add unit test to cover the vote key format
* add gapNumber to the vote pool key
* fix race condition in pool
* remove verify gap number in vote handler
