yt-dlp's own test suite marks channel sort as 'Query for sorting no
longer works' — YouTube blocked it. New approach: fetch view_count for
up to 200 indexed videos in parallel (8 workers, prioritising those
missing counts), then Popular tab sorts by view_count DESC WHERE
view_count IS NOT NULL. Accurate for any channel once enrichment runs.
Frontend refetch wait raised to 60s to cover ~200 parallel fetches.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>