Add `rooms add` propagation protection prompt, to prompt to protect a room after being invited if it isn't already protected.

[Gnuxie]

Do the same when being kicked from rooms by people in the management room.

Essentially this means that a Draupnir user doesn't even have to use the rooms add command, they can just invite the bot, set the permissions and click the prompt. We'd probably want to pair this with the "accept invites from space" config so that it is consistent with it and prompts whenever an authorized invitation is received.