watch configuration and auto reload

[CSUwangj]

I got some question about this feature:

0. is it necessary, or best to have, or just a drug of my fantasy?
1. according to https://vorner.github.io/2019/08/11/runtime-configuration-reloading.html, seems using signal is more user friendly to edit operation, but windows don't have SIGHUP.
2. what should it do when the configuration changes, or how it could be reloaded?
3. then should we add auto-reload file content into it? then maybe we should read a resource at starting, seems ugly?

[CSUwangj]

by asking these questions, I found I'm not sure about this feature, so I decide to save it for later, and archive the card.