Upon disconnect, allow the client to remain open and return to login screen

Imported from legacy Flarum.
Original author: EvilLumi (Flarum #372)

Please. For me, and a few others who require to log back into their accounts. It’s also super annoying as a standard thing. I understand sometimes it requires us to patch things, but allow us to control how that happens, and when it happens. Thank you for reading.