Ability to ban a user from every room I can

Your use case

What would you like to do?

I want to ban a particular user from all rooms I have the necessary power level to do so.

Why would you like to do it?

There's a particular account @daley_:matrix.org that has been going around many rooms for a while now and despite clicking report a few times, the matrix.to admins don't seem to be in a hurry to ban the account:

We have lots of rooms in our space and as far as I can tell the only way to preemptively ban the user everywhere is to go into every single room and run /ban @daley_:matrix.org according to vector-im/element-web#10516.

I don't even see a UI to ban the user from the channels under our space (#6829) unless the account actually joins the space (our channels are publicly visible for easier discoverability).

How would you like to achieve it?

If you are at a point where you want to ban a user, it's very likely you don't want to deal with them in any other of your channels, so this should be an easily accessible top level function:

.

It's also likely that you want to remove all recent messages from them in all rooms you can without going through every room one by one.

Have you considered any alternatives?

No response

Additional context

No response

The issue names no files, tests, or implementation entry points. Start by reviewing the referenced element-web#10516 and #6829 discussions, then determine the affected client and Matrix operations. Done means agreeing on the scope for banning a user across eligible rooms and handling their recent messages.