Add new EQUIPMENT, STAFFING, and CLOSED request statuses and associated logic.

[nopivnick]

if a request does not include staffing or equipment:

• a booking with status REQUESTED that's pre-approved should be assigned status PENDING and appear in the Admin context bookings table
• requests with status CANCELED, DECLINED, or NO SHOW should automatically be assigned status CLOSED

if a request includes staffing:

• a booking with status REQUESTED that's pre-approved should be assigned status STAFFING and appear in the STAFFING context bookings table with the actions "Approve" or "Decline"

if a request includes equipment:

• a booking with status REQUESTED that's pre-approved should be assigned status EQUIPMENT and appear in the Equipment context bookings table with the Action "Approve" or "Decline"
• requests with status CANCELED, DECLINED, or NO SHOW should re-appear in the Equipment context booking table with the action "Equip. Approval"; after taking the "Equip. Approval" action the request should be assigned status CLOSED