feat: one Missing files page under Collection: folders gone, each with its album's want, last search or download, and Search, Releases and Remove; an album held before its files went is no longer shown as held again (M504 #5626)

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

internal/db/queries/wanted.sql

@@ -177,7 +177,8 @@ DELETE FROM wants WHERE id = $1;
 
 -- name: ListWants :many
 -- The Wanted page: open wants (all but missing ones, or only missing ones),
--- the held ones, or all of them; artist_mbid narrows to one artist's page. Ordered like the library (#5572): artists A–Z by the
+-- the held ones, or all of them; artist_mbid narrows to one artist's page,
+-- want_ids to given wants. Ordered like the library (#5572): artists A–Z by the
 -- library's sort name when it holds the artist, each artist's albums by
 -- release date, so the page groups them as they arrive. q narrows to an
 -- artist or album title; total counts every match, past the page.
@@ -216,6 +217,8 @@ SELECT w.id, w.release_group_mbid, w.artist_mbid, w.artist_name, w.title, w.reas
          ELSE                w.fulfilled_at IS NULL AND w.reason <> 'missing'
        END
    AND (sqlc.arg(artist_mbid)::text = '' OR w.artist_mbid = sqlc.arg(artist_mbid)::text)
+   -- want_ids narrows to given wants: the Missing page's folders (M504).
+   AND (COALESCE(cardinality(sqlc.arg(want_ids)::uuid[]), 0) = 0 OR w.id = ANY(sqlc.arg(want_ids)::uuid[]))
    AND (sqlc.arg(q)::text = ''
         OR strpos(lower(w.artist_name), lower(sqlc.arg(q)::text)) > 0
         OR strpos(lower(w.title), lower(sqlc.arg(q)::text)) > 0)