change(backend): nur noch der erste Kuenstler im Dateinamen

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

backend/novasonic-server.js

@@ -18,7 +18,7 @@ const crypto         = require('crypto');
 
 const CONFIG    = require('./lib/config');
 const { jobs, updateJob, log } = require('./lib/jobs');
-const { sanitize, findExistingTrack, findFileByStem, albumDirFromTags } = require('./lib/metadata');
+const { sanitize, findExistingTrack, findFileByStem, albumDirFromTags, dateinamensKuenstler } = require('./lib/metadata');
 const dz = require('./lib/deezer');
 const tm = require('./lib/trackmeta');   // Deezer → MusicBrainz → clean fallback (single tracks)
 const { downloadTrack, downloadAlbumTracks } = require('./lib/downloader');
@@ -1553,7 +1553,7 @@ app.post('/api/edit-metadata', async (req, res) => {
     // Use original names (may be Japanese); romaji goes only into sort tags.
     if (title) {
       const safeTitle      = sanitize(title);
-      const fileArtist     = (normalArtist || ndSong?.artist || '').replace(/;/g, ',');
+      const fileArtist     = dateinamensKuenstler(normalArtist, ndSong?.artist);
       const safeArtistPart = fileArtist ? sanitize(fileArtist) + ' - ' : '';
       const prefix         = trackNum ? String(trackNum).padStart(2, '0') + ' - ' : '';
       const newName        = `${prefix}${safeArtistPart}${safeTitle}${fileExt}`;