Re-add debounce to fsnotify

[mpscholten]

The latest version of fsnotify has removed debouncing from the library, so we likely need to implement this ourselves.

Related to #1771

[amitaibu]

I suspect this is also causing a longer time waiting for the server to start, as it's re-compiling the same code over and over again - like after git pull

[mpscholten]

Yes 👍

[amitaibu]

I think this library has implemented the debounce that was removed, and is built on top of fsnotify

https://hackage.haskell.org/package/steeloverseer-2.1.0.1/docs/System-FSNotify-Streaming.html