Offer a waitlist spot when something opens up

Open Menu, then CLIENTS & BOOKINGS, then Waitlist. It is grouped into Waiting, Offered, and Claimed or expired.

When a cancellation frees up a slot, offer it to someone in Waiting. Once they take it, Mark claimed moves them out. Back to waiting puts someone back if the offer fell through, so a no-reply does not lose their place.

Removing someone asks "Remove from waitlist?" first.