refactor(server/sql): unify *ForUser track queries via nullable user_id (A1)

internal/db/queries/tracks.sql

@@ -26,23 +26,9 @@ SELECT * FROM tracks WHERE id = $1;
 SELECT * FROM tracks WHERE file_path = $1;
 
 -- name: ListTracksByAlbum :many
-SELECT * FROM tracks WHERE album_id = $1 ORDER BY disc_number NULLS LAST, track_number NULLS LAST;
-
--- name: CountTracksByAlbum :one
-SELECT count(*) FROM tracks WHERE album_id = $1;
-
--- name: SearchTracks :many
-SELECT * FROM tracks
-WHERE title ILIKE '%' || $1 || '%'
-ORDER BY title
-LIMIT $2 OFFSET $3;
-
--- name: CountTracksMatching :one
-SELECT COUNT(*) FROM tracks WHERE title ILIKE '%' || $1::text || '%';
-
--- name: ListTracksByAlbumForUser :many
--- Same as ListTracksByAlbum but excludes tracks the user has quarantined.
--- $1 = album_id, $2 = user_id.
+-- $1 = album_id, $2 = user_id. Pass pgtype.UUID{Valid: false} (NULL)
+-- to skip the per-user quarantine filter; the NOT EXISTS clause on
+-- a NULL user_id never matches a row, so every track passes through.
 SELECT * FROM tracks
 WHERE album_id = $1
   AND NOT EXISTS (
@@ -51,10 +37,14 @@ WHERE album_id = $1
   )
 ORDER BY disc_number NULLS LAST, track_number NULLS LAST;
 
--- name: SearchTracksForUser :many
--- $1 = title query, $2 = user_id, $3 = limit, $4 = offset.
+-- name: CountTracksByAlbum :one
+SELECT count(*) FROM tracks WHERE album_id = $1;
+
+-- name: SearchTracks :many
+-- $1 = title query, $2 = user_id (NULL to skip quarantine filter),
+-- $3 = limit, $4 = offset.
 SELECT * FROM tracks
-WHERE title ILIKE '%' || $1 || '%'
+WHERE title ILIKE '%' || $1::text || '%'
   AND NOT EXISTS (
     SELECT 1 FROM lidarr_quarantine q
     WHERE q.user_id = $2 AND q.track_id = tracks.id
@@ -62,8 +52,8 @@ WHERE title ILIKE '%' || $1 || '%'
 ORDER BY title
 LIMIT $3 OFFSET $4;
 
--- name: CountTracksMatchingForUser :one
--- $1 = title query, $2 = user_id.
+-- name: CountTracksMatching :one
+-- $1 = title query, $2 = user_id (NULL to skip quarantine filter).
 SELECT COUNT(*) FROM tracks
 WHERE title ILIKE '%' || $1::text || '%'
   AND NOT EXISTS (