Forgejo was supposed to, but that feature has been in limbo forever. For better or worse, ATProto is easier to implement, because most of the important details of ActivityPub are undocumented compatibility details of implementations like Mastodon (the spec alone isn't very useful for a working, compatible implementation).

AI would make it easier to implement and test complex protocols like this, but the community using Forgejo is mostly against it, which means it'll likely stay in limbo for a long time.