Add a "Smart Auto-Assign" option when auto-assigning

The assignment should be as follows:

Reservation of 1 person
1. look for a bed with a guest departing on the same day as the reservation to be assigned, in order to avoid gaps.
2. from among the options, look for a bunk bed with a guest departing on the same day as the reservation to be assigned. (We look for bunk beds with both guests departing on the same day as far as possible).

Group reservation
1. group together in the same room.
2. Within the possible options, we go to point 1 and 2 of the 1 person reservation.