I can’t help you but I’m fascinated by your door now. Does this door/lock have a name? How did you end up with such an elaborate mechanism?

I’ve used 3 unrelated baby cams and junked them all because not one was remotely usable, never mind reliable.

That was a decade ago, but we had pretty solid ip cameras a decade ago.

Absolutely, there are a good few window managers designed to be standalone. I use AwesomeWM and i3 is very popular.

If you don’t need a full desktop environment it’s nice to have something that mostly stays out of the way.