feat: search and grab — music release names, a quality ladder, a paced search schedule and one live grab per want (M502 #5521)

- internal/release: reads a release name (format, bitrate, bit depth and
  sample rate, source, year, video, discography) and judges it against the
  album wanted: the artist and title must be in it; video rips,
  discographies, other versions (drumless, instrumental, karaoke, remix,
  live unless the album is live…) and singles or EPs for an album are
  refused. Quality tiers on Lidarr's ladder; a .torrent's file list is read
  for format, video files and a track count short of the album.
- internal/acquire: fan-out across every search source with a narrowed
  search kept, a process-wide pacer per source, every candidate judged and
  kept with its reasons, and the grab: one live grab per want, tie-broken
  (a person's grab beats the schedule's; a better release replaces a worse
  one unless it is nearly done). Each download lands in its own folder
  under the client's downloads folder.
- internal/wanted: the search schedule, every ten minutes, never-searched
  first, then requests, missing files and followed artists, taking the
  best release when auto-grab is on (the default).
- Migration 0082: acquisition_settings (auto-grab, interval, allowed
  qualities seeded from Lidarr's "Any"), want search columns,
  want_candidates, grabs, release_blocks.
- Web: the Wanted page shows each want's last search, a Search button and
  every release found with its verdict (Grab, Grab anyway, Never this one,
  Allow again). Integrations gains "Searching and grabbing".

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

cmd/minstrel/main.go

@@ -322,6 +322,12 @@ func run() error {
 	// daily for new releases and marks wants held once the library has them.
 	go wanted.New(pool, cat, logger.With("component", "wanted")).Run(ctx)
 
+	// Search and grab (M502 #5521): every ten minutes, searches the
+	// configured indexers for wants due, paced by each source's
+	// searches-per-hour, and hands the best release to the download client
+	// when auto-grab is on.
+	go wanted.NewSearcher(pool, cat, logger.With("component", "search")).Run(ctx)
+
 	// Duplicate resolver (M498, M502): classifies the sweep's groups and, with
 	// the operator's auto-resolve on, merges the copies that are safe to merge.
 	// Started after SetNotifier so its summaries reach admins. See