I’ve been using the Jellyfin WebOS app, it works well but sometimes will transcode instead of direct streaming the first time something is played. Restarting a few times fixes it though. I also have jellyfin on my steam deck, but I don’t think it does drm apps.
Forgejo has an option to mirror a repository and update on a regular interval. It won’t get wikis or issues though. I’ve got mine set up to mirror a bunch of decomps.