Co-authored publications #31

This would be a kinda complex one that honestly borders on an unsolved problem in the ATmosphere, but it would be really nice if multiple users/bsky accounts could publish posts to the same Leaflet publication - it'd be much easier and cleaner than having to collectively juggle one AT account to publish on. This could maybe be done with one account storing the publication in their repo and having a list of DIDs authorized to post additional stuff to it? Either way it'd be a huge leap forward.