Allow managers of indico events to associate an existing room booking to that event

Is your feature request related to a problem? Please describe.
I am managing several indico events and room bookings these days. There is a somewhat confusing feature presently:

• In the management of indico events, the 'room booking' tab shows if a room booking is associated to the event, or otherwise allows event managers to book a room. However it does not allow them to associate the event to an existing room booking.
• Similarly existing room bookings display whether they are associated to an existing event. But there is no interface to associate the room booking to an event (or delete the association if it is stale).
• This is confusing because the room booking that is shown has nothing to do with the room where the event is indicated to take place (and which is itself often associated to the possibility to connect that room to zoom). So one may end up having two rooms associated to an event, a visible one (that can be changed) and a somwhat hidden one (that only shows up in some interfaces and can sometimes be added but not changed).

Describe the solution you'd like
One possible solution would be to allow event managers to associate existing room bookings to their event, and similarly to remove existing associations to room bookings which may have become stale or obsolete.
(This would still leave open the issue that there could be two rooms associated to an event, but this may be complex to fix).

Describe alternatives you've considered
A simpler and more radical alternative would be to completely remove the "association" of a room booking to an indico event. As I mentioned, this is NOT the room that shows up as the place where the event takes place, and is in itself of debatable usefulness. It may often just add confusion.

Additional context
None.

No files, tests, or entry points are named, so first locate the event-management and room-booking association flows. Define how event managers can associate an existing booking and remove a stale association, then verify both interfaces reflect the change and clarify behavior when two rooms are associated.