Adds 4 new models for grand-finale logistics PR 1:
- FinalistSlotQuota: per-category mutable quotas
- WaitlistEntry: ranked per-category waitlist
- FinalistConfirmation: token-gated confirmation lifecycle (PENDING /
CONFIRMED / DECLINED / EXPIRED / SUPERSEDED) with optional decline reason
- AttendingMember: who from each team is attending, with visa flag
Plus Program.defaultAttendeeCap (default 3) for the per-edition team
attendance cap.
Migration is purely additive: no DROP/ALTER COLUMN/RENAME on existing
schema. All FKs ON DELETE CASCADE only fire on parent deletion.
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