fix: romaji override delete button (JSON.stringify breaks HTML attr); fix file stem search for en-dash track prefixes

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

backend/novasonic-server.js

@@ -95,19 +95,31 @@ function _findFileInDir(dir, basename) {
 // Convention: MusicRoot/AlbumArtist/Album/{01 - }Artist - Title.ext
 // The title stem is everything after the optional "NN - Artist - " prefix.
 // We match any audio file whose stem ends with the same title words.
+// Normalize a file stem for loose matching:
+// 1. Strip compound track prefixes like "01-15 – " or "01 - " (handles en-dash, em-dash, hyphen)
+// 2. Normalize all dash variants (en-dash, em-dash) to " - "
+function _normStem(s) {
+  return s
+    .replace(/^\d[\d\-–—]*\s*[-–—]\s*/, '') // strip leading "01-15 – " or "01 - "
+    .replace(/\s*[–—]\s*/g, ' - ');          // normalize remaining en/em-dash to " - "
+}
+
 function _findFileByStem(dir, titleStem, depth = 0) {
   if (depth > 4) return null;
+  const normTitle = _normStem(titleStem);
   try {
     for (const entry of fs.readdirSync(dir, { withFileTypes: true })) {
       if (entry.isDirectory()) {
         const found = _findFileByStem(path.join(dir, entry.name), titleStem, depth + 1);
         if (found) return found;
       } else if (AUDIO_EXT_RE.test(entry.name)) {
-        // Strip extension, strip leading "NN - ", then strip optional "Artist - " prefix
-        const bare = entry.name.replace(AUDIO_EXT_RE, '').replace(/^\d+\s*-\s*/, '');
-        // bare may be "Artist - Title" or just "Title" — match from the end
-        const bareStem = bare.toLowerCase();
-        if (bareStem === titleStem || bareStem.endsWith(' - ' + titleStem) || bareStem.endsWith(titleStem)) {
+        // Strip extension + leading track prefix, then normalize dashes
+        const bare     = entry.name.replace(AUDIO_EXT_RE, '').replace(/^\d+\s*-\s*/, '');
+        const bareStem = _normStem(bare.toLowerCase());
+        // Match: exact, or "Artist - Title" ending with our title stem
+        if (bareStem === normTitle ||
+            bareStem.endsWith(' - ' + normTitle) ||
+            bareStem.endsWith(normTitle)) {
           return path.join(dir, entry.name);
         }
       }