Central settings panel to manage avatar/nick overrides

[ShadowJonathan]

Is your suggestion related to a problem? Please describe.

Currently when I want to manage my nickname and avatar per room, i'll have to go to that specific room to observe and possibly make changes there via a command.

Describe the solution you'd like.

I'd like there to be a single panel where I can observe all avatar/nick "overrides", and also change per room, or a selection of rooms (possibly also per space).

Additional context

Some inspiration;

(Discord, Notification settings per server)

[t3chguy]

Duplicate of element-hq/element-meta#499

The current implementation doesn't cut the mustard hence that issue remains open.