you basically need to bootup gitea-scale services

Is that actually difficult though? I was always under the impression that Gogs/Gitea were pretty easy to run because they're also written in Go.

I just checked Gogs and it looks like it has exactly the same dependencies as Git-PR (Git and and SSH server).

It would definitely be cool if Gogs/Gitea/Gitlab/Sourcehut standardised a PR API, but... like properly.