Enrich owned artists whose discography hasn't been fetched yet in a
bounded, resumable background pass so their wider catalogue is searchable
offline right after a scan, instead of only on first artist-page view.
Keyed off the persistent discog_fetched flag via LEFT JOIN, so already-
enriched artists never reappear and the run is a cheap no-op once every
owned artist is covered. Capped at discogBackfillMaxPerRun per run and
routed through discogSF to avoid double-fetching an artist a concurrent
interactive EnsureArtistDiscography is handling. Invoked on both scan
completion (OnStartup) and OnDomReady to resume a capped/interrupted run.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>