new 'Download YouTube Wishlist' automation: pushes a polite batch of wished
youtube videos into the shared video_downloads queue + spawns the yt-dlp worker
per video. skips in-flight ones (no double-grab); big backlogs drain over
several scheduled runs (batch_size, default 3). needs the youtube library folder
set.
- download_monitor: SKIP source='youtube' rows (owned by their worker thread, no
slskd transfer to match) — surgical, slskd path untouched.
- db.youtube_wishlist_to_download(): flat newest-first list of wished videos with
channel/title/date/thumb for organising.
block + registration + icon/label + drift test. all seam-tested.
