Tests now guard against accidental drop of kartsell_migration_test by throwing
when the credential source DB is the destructive rehearsal target. Distinct
credential DB (kartselldb_test) prevents config collision.
AEG-X-004 evidence consolidated: rehearsal .trx files + preflight markdown
documented. Schema 0032 (shadow_run_queued_status_contract) verified
fresh/upgrade/recovery on isolated DB.
AGENTS.md: Necessity-driven (guard against destructive accident); no new feature.
Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>
kjh2064