Thanks for a such detailed review of forgejo actions. Did you check dead simple ci? This is forgejo runner supporting direct general purposes languages syntax instead of yaml for your pipelines, so much easier to write scripts for any custom scenarios and not to be lost down rabbit ( yaml ) hole . I guess your case is pretty much covered with using custom fedora image and then just throwing a few shell tasks . If your interest we have a demo server to play with and I can help you with Fedora QA tasks repository pipeline setup.
http://deadsimpleci.sparrowhub.io/doc/demo~ Alexey