Yes plz. I'd be very interested to read about this (long time Debian user, but never packaged anything).

I know there is an install, postinstall, and remove scripts but don't have a clear idea of when exactly they will get called and what "interface" they must implement.

It would be really helpful to have a "package lifecycle" state diagram like this https://vuejs.org/v2/guide/instance.html#Lifecycle-Diagram that shows all the states and events that "fire" based on .deb scripts and metadata.