Send the PART command to remote servers
Don't filter the user list when we receive a server command
Only registered users are meant to be propagated (including at burst)
The default "to" parameter for remote messages should be the user's UUID, not nick
Actually propagate user messages across servers
Don't send additional channel messages directly to remote users
Fix how servers process status modes
Fix status mode sending over server connections
Fix list splitting on unset for custom prefixes
Fix it for the core statuses, too
Since remote servers only know about registered users, only send QUITs for registered users