- backup.tla: models backup/restore/verify/cleanup with properties:
BackupSnapshotsValid, RestoreIntegrity, VerifyIntegrity,
RetentionInvariant, HistoryConsistency, BackupIdValid
- recovery.tla: models WAL replay REDO/UNDO with properties:
RedoCommitted, RecoveryCompleteness, WalIntegrity
- Added models/backup.cfg and models/recovery.cfg with bounded constants
- Updated run_all.sh to include both new specs
- All 9 TLA+ specs pass TLC model checking