I should be able to view My Spaces by most-recently-used

(User Story, Investigate , Priority: High, Test Status: No automated tests yet , Reported By Justin du Coeur, )

Summary: It's silly that this is still only visible in creation order.

Note that this depends on SpaceMembership.lastAccess, which was created way back in 6.sql. We should set this when we start or finish the UserSpaceSession.

We will need to query this in the query for My Spaces, and propagate it to the client.