StaleMediaIDRepository.Upsert inserts (content_id, provider, ...) into
stale_media_ids, which has a foreign key to media_items.content_id. A
metadata refresh can start for an item that is then deleted or merged
away (e.g. by provider-ID canonicalization) before the provider 404
lands and triggers the upsert. The parent row is gone by then, so the
insert fails with a 23503 foreign-key violation
(stale_media_ids_content_id_fkey) and the refresh surfaces a spurious
error — observed in production postgres logs.
When the referenced item no longer exists there is nothing left to track,
so treat that specific FK violation as a logged no-op (at Info, with
provider_id, so a deletion wave stays visible). Other errors still
propagate. The swallow decision is extracted to resolveStaleUpsertError so
it is unit-testable without a database, and the pgconn error-classification
boilerplate is consolidated into a shared isPgConstraintViolation helper
that isProviderIDUniqueConflict now also uses.
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
