fix: romaji for album names + Japanese playlist track matching

- ytdlp.js + novasonic-server.js: apply romajiForStorage to album tag
  and folder/rename paths (was only applied to artist/title before)
- ui.js: _createNdPlaylist falls back to romaji index for Japanese titles
  since Navidrome search3 doesn't index Japanese text properly

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/lib/ytdlp.js

@@ -53,8 +53,9 @@ async function downloadTrack({ jobId, artist, albumArtist, title, album, year, t
   const mainArtistRomaji = romajiForStorage(mainArtist) || mainArtist;
   const artistRomaji     = romajiForStorage(artist)     || artist;
   const titleRomaji      = romajiForStorage(title)      || title;
+  const albumRomaji      = album ? (romajiForStorage(album) || album) : null;
   const safeArtist = sanitize(mainArtistRomaji.split(/[,;&]/)[0].trim());
-  const safeAlbum  = sanitize(album || 'Singles');
+  const safeAlbum  = sanitize(albumRomaji || 'Singles');
   const dir = path.join(outputDir || CONFIG.musicPath, safeArtist, safeAlbum);
   fs.mkdirSync(dir, { recursive: true });
 
@@ -306,6 +307,7 @@ async function embedMetadata({ jobId, audioFile, dir, trackPrefix, safeTitle, ar
     const storedTitle       = romajiForStorage(title)                                       || title;
     const storedArtist      = romajiForStorage(navidromeArtist(artist))                    || navidromeArtist(artist);
     const storedAlbumArtist = romajiForStorage(mainArtist.replace(/\s+&\s+/g, ', '))       || mainArtist.replace(/\s+&\s+/g, ', ');
+    const storedAlbum       = album ? (romajiForStorage(album) || album) : null;
     ffArgs.push(
       '-c',             'copy',
       '-map_metadata',  '-1',
@@ -314,7 +316,7 @@ async function embedMetadata({ jobId, audioFile, dir, trackPrefix, safeTitle, ar
       '-metadata', `artist=${storedArtist}`,
       '-metadata', `album_artist=${storedAlbumArtist}`,
     );
-    if (album)       ffArgs.push('-metadata', `album=${album}`);
+    if (storedAlbum) ffArgs.push('-metadata', `album=${storedAlbum}`);
     if (year)        ffArgs.push('-metadata', `date=${String(year)}`);
     if (trackNum)    ffArgs.push('-metadata', `track=${totalTracks ? `${trackNum}/${totalTracks}` : String(trackNum)}`);
     if (totalTracks) ffArgs.push('-metadata', `totaltracks=${String(totalTracks)}`);

backend/novasonic-server.js

@@ -613,6 +613,7 @@ app.post('/api/edit-metadata', async (req, res) => {
   const romajiArtist      = normalArtist      ? romajiForStorage(normalArtist)      || normalArtist      : normalArtist;
   const romajiAlbumArtist = normalAlbumArtist ? romajiForStorage(normalAlbumArtist) || normalAlbumArtist : normalAlbumArtist;
   const romajiTitle       = title             ? romajiForStorage(title)             || title             : title;
+  const romajiAlbum       = album             ? romajiForStorage(album)             || album             : album;
 
   // Resolve file path from Navidrome
   let filePath;
@@ -682,7 +683,7 @@ app.post('/api/edit-metadata', async (req, res) => {
       if (romajiArtist)      ffArgs.push('-metadata', `artist=${romajiArtist}`);
       const resolvedAlbumArtist = romajiAlbumArtist || (romajiArtist ? romajiArtist.split(';')[0].trim() : null);
       if (resolvedAlbumArtist)   ffArgs.push('-metadata', `album_artist=${resolvedAlbumArtist}`);
-      if (album)       ffArgs.push('-metadata', `album=${album}`);
+      if (romajiAlbum) ffArgs.push('-metadata', `album=${romajiAlbum}`);
       if (year)        ffArgs.push('-metadata', `date=${year}`);
       if (trackNum)    ffArgs.push('-metadata', `track=${totalTracks ? `${trackNum}/${totalTracks}` : String(trackNum)}`);
       if (totalTracks) ffArgs.push('-metadata', `totaltracks=${String(totalTracks)}`);
@@ -724,7 +725,7 @@ app.post('/api/edit-metadata', async (req, res) => {
     // 2. Move to new artist/album folder when albumArtist or album changed
     const oldAlbumDir  = path.dirname(currentFile);
     const oldArtistDir = path.dirname(oldAlbumDir);
-    const newAlbumName  = album             ? sanitize(album) : path.basename(oldAlbumDir);
+    const newAlbumName  = romajiAlbum       ? sanitize(romajiAlbum) : path.basename(oldAlbumDir);
     const newArtistName = romajiAlbumArtist ? sanitize(romajiAlbumArtist.split(/[,;&]/)[0].trim()) : path.basename(oldArtistDir);
     const newDir = path.join(CONFIG.musicPath, newArtistName, newAlbumName);
 
@@ -746,9 +747,9 @@ app.post('/api/edit-metadata', async (req, res) => {
           } catch {}
         }
       } catch (e) { console.error('[edit-metadata] move:', e.message); }
-    } else if (album && path.basename(oldAlbumDir) !== sanitize(album)) {
+    } else if (romajiAlbum && path.basename(oldAlbumDir) !== sanitize(romajiAlbum)) {
       // Only album name changed (no artist move) — rename album folder in place
-      const renamedDir = path.join(oldArtistDir, sanitize(album));
+      const renamedDir = path.join(oldArtistDir, sanitize(romajiAlbum));
       if (!fs.existsSync(renamedDir)) {
         try { fs.renameSync(oldAlbumDir, renamedDir); }
         catch (e) { console.error('[edit-metadata] folder rename:', e.message); }