You can write custom c++ modules for bits they don't have already, although that's pretty rare. Often used with HA but it works fine standalone with MQTT too, and deployment doesn't have to be from a server.
A simple pull reel was my goto, but that doesn't work in this application. Amazing work very smart and looks like a fun project.
(Also, I don't think you can do it by edit, but next time note that you can submit both a URL and some accompanying text.)
This is exactly what I thought. I downvoted (now removed) thinking that it was a random passerby being dismissive.
Edit: cool project, well done!