I was going to mention that rooms manager app, but you beat me to it. Rooms Manager: Smarter Rooms: Personalized home automation with Occupancy
Maybe that could be maintained or forked by someone? It appears to be abandoned at this point, the author hasn't logged in since 2023.
This app actually works pretty well, and is very sophisticated in how it can be used. It would be nice if this were a built-in app that leveraged the existing room concept.
