A GitHub release scan that hit a transient asset error still saved the release-list ETag, so the failed asset was never retried. Assets that are corrupt, deleted or truncated upstream fail on every retry, so they must not keep the remote failed.
- fail the rpm/deb/alpine scan on transient asset fetch, short read or metadata insert errors, so the ETag is not saved and the backoff retry re-derives the asset
- add `provider.ErrInvalidPackage` for unparseable packages and 404/410/416 asset downloads; such assets are logged and skipped
- decide a ranged fetch holds the whole object from Content-Length or the Content-Range total, or a clean EOF when the total is unknown
- add a NOT VALID cascading FK from the GitHub sync-state tables to `remotes`
Reviewed-on: #135
Co-authored-by: unkin-agent <unkin-agent@unkin.net>
Co-committed-by: unkin-agent <unkin-agent@unkin.net>
Releasing a GitHub sync lease always advanced `last_synced_at`, even after a failed scan (e.g. a rate-limit 403). A remote that failed once waited a full `mutable_ttl` before retrying, and a cold remote kept returning 503 until then.
- record scan outcomes in one shared lease helper for github_rpm/deb/alpine
- keep `last_synced_at` and the ETag on failure; retry from 60s with exponential backoff, capped at min(10m, ttl/4)
- honour `Retry-After` / `X-RateLimit-Reset`, clamped to `mutable_ttl`
- add `sync_failures` / `next_retry_at` columns (migration 0002)
Reviewed-on: #133
Co-authored-by: unkin-agent <unkin-agent@unkin.net>
Co-committed-by: unkin-agent <unkin-agent@unkin.net>
unkin-agent