Ambiguous idempotency-store failures can occur after the account transaction commits. Scope durable recovery markers to the authenticated admin, retain the operation key across reloads, and recover only an already committed copy without rerunning active work.
Constraint: Generic idempotent handlers may legitimately remain active while a recovery lookup is attempted
Rejected: Reclaim or rerun an in-progress duplicate request | can execute account creation concurrently
Rejected: Recover by source account and key alone | allows another admin to observe the committed copy
Confidence: high
Scope-risk: narrow
Reversibility: clean
Directive: Keep ambiguous-response recovery read-only and bind durable operation markers to the authenticated actor
Tested: Full Go unit suite, go vet, server build, integration-test compilation; frontend lint, typecheck, 1,030 Vitest tests, and production build
Not-tested: Docker-backed PostgreSQL integration runtime because Docker is unavailable
Related: Wei-Shaw/sub2api#1379
Related: Wei-Shaw/sub2api#2928
yan9651688