[Feature] Redirect remote user to internal ID
Resolve remote user's host name and user name into internal ID, and redirect to that.
Some implementations of decentralized social network, such as Misskey, have no explicit remote follow feature on their standard web UI. In case of following from Pleroma (e. g.
pleroma.example.com) to Misskey (e. g.
firstname.lastname@example.org), first we can open the URL
https://pleroma.example.com/remote-user/@email@example.com, redirected into
https://pleroma.example.com/users/INTERNAL_ID, and we can push the follow button.