Backend:
- New error_log table: url, domain, error, format_id, media_type,
session_id, created_at
- log_download_error() called when yt-dlp throws during download
- GET /admin/errors returns recent entries (limit 200)
- DELETE /admin/errors clears all entries
- Manual purge also clears error log
- Domain extracted from URL via urlparse for grouping
Frontend:
- New 'Errors' tab in admin panel (Sessions, Storage, Errors, Settings)
- Each error entry shows: domain, timestamp, full URL, error message,
format/media type metadata
- Red left border + error-colored message for visual scanning
- Clear Log button to wipe entries
- Empty state: 'No errors logged.'
Error entries contain enough context (full URL, error message, domain,
format, media type) to paste into an LLM for domain-specific debugging.