feat: a wanted list — follow artists on release-type profiles; requests and re-acquisition become wants (M502 #5520)

Minstrel keeps its own list of what it is to get, keyed by MusicBrainz
release group. A want comes from an approved request, a new release by a
followed artist, or an album whose files went missing, and is held once the
library has a full edition of it.

- Migration 0081: release_type_profiles (Standard seeded: Album, EP,
  Single, studio only), follows, follow_seen_groups and wants.
  lidarr_requests becomes requests with plain *_mbid columns; approved
  album and track requests move onto the wanted list, approved artist
  requests become follows, and the library's album artists start out
  followed. missing_reacquisitions and the retry settings go.
- internal/wanted: follows are checked against MusicBrainz discographies
  daily. The first check sets a baseline, and only releases after it are
  wanted unless the follow asked for what already exists. Profiles filter
  by primary and secondary type, so live recordings stay out unless a
  profile ticks Live.
- internal/requests (was lidarrrequests): approving puts the request on
  the wanted list, and an artist request can be approved on a chosen
  profile. A request completes when its want is held.
- The re-acquisition sweeper wants a missing album back instead of asking
  Lidarr; searching for it is the search schedule's (#5521).
- Web: an admin Wanted page (Wanted, Missing files, Held, Following), a
  follow control on artist pages, a release-type profiles card on
  Integrations, "Approve on a profile" on Requests, and want state on
  Missing files. The artist detail API returns the artist's MBID.
- Android: the request body sends artist_mbid, album_mbid and track_mbid.

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

internal/catalogue/catalogue.go

@@ -66,6 +66,13 @@ type Discography struct {
 // DiscographyMaxAge. When MusicBrainz is unreachable, a copy already held is
 // returned marked Stale; with nothing held, the error is returned.
 func (s *Service) Discography(ctx context.Context, artistMBID string) (Discography, error) {
+	return s.DiscographyWithin(ctx, artistMBID, DiscographyMaxAge)
+}
+
+// DiscographyWithin is Discography with the age past which the held copy is
+// read again: a followed artist is checked for new releases more often than
+// one the catalogue merely knows.
+func (s *Service) DiscographyWithin(ctx context.Context, artistMBID string, maxAge time.Duration) (Discography, error) {
 	q := dbq.New(s.pool)
 	artist, err := q.GetMBArtist(ctx, artistMBID)
 	held := err == nil && artist.DiscographyRefreshedAt.Valid
@@ -73,7 +80,7 @@ func (s *Service) Discography(ctx context.Context, artistMBID string) (Discograp
 		return Discography{}, fmt.Errorf("catalogue: read artist: %w", err)
 	}
 	stale := false
-	if !held || s.now().Sub(artist.DiscographyRefreshedAt.Time) > DiscographyMaxAge {
+	if !held || s.now().Sub(artist.DiscographyRefreshedAt.Time) > maxAge {
 		if rerr := s.RefreshArtist(ctx, artistMBID); rerr != nil {
 			if !held || !errors.Is(rerr, musicbrainz.ErrUnreachable) {
 				return Discography{}, rerr