docs: extreme-detail reference for SA bookings, passes, scheduling, waitlist, transfers

Classic hourly booking form, booking passes (confirmed orphaned gate-scan
API), daily/weekly schedule, blackout dates, conflict detection scope,
locker rentals, group schedule/waitlist/transfer (including the separate
TrainingGroups parallel system), makeup sessions, and Service Desk. Flags
a consistent cash-collected-outside-the-system pattern across three
screens for a deliberate finance decision rather than three silent fixes.