# F-177 — Implementer

- Migration 051 adds indexed `state_changed_at`, backfilled from `updated_at`.
- Repository and payment state transitions now update that timestamp; edits unrelated to state do not reset the 24 h clock.
- New admin-only `GET /orders/notifications/stale` returns PENDING/SHIPPED orders older than threshold, total count, customer, amount and elapsed hours.
- Header bell includes count badge, accessible dropdown, status/age/amount, direct links, empty/error/loading states, 5-minute polling, manual refresh, Escape and outside-click closing.

Evidence: migration applied; project typecheck PASS; order tests 7/7; Admin Next build PASS; authenticated endpoint HTTP 200. Controlled acceptance row at 25 h returned total=1/state=PENDING/ageHours=25, then database row was restored.