A deployment branch can fail a guarded migration check when it shares a database

A deployment branch can fail a guarded migration check when it shares a database with another branch that has already applied a newer additive migration. Reconcile the branch's source history to the exact approved migration artifact and schema contract, validate the live ledger frontier read-only, and let the normal guarded workflow run. If the new enum value also has a runtime validation registry, classify it there so the complete CI gate catches source drift. This method applies when the already-applied migration is proven identical and additive; it does not justify editing old ledger rows or asserting full historical parity.