fix: case-insensitive title filter + scan before playlist creation

backend: replace title *= (case-sensitive) with title ~= (?i) regex so
"MEMORIES" and "Echoes of Eternity" match regardless of YT title casing.
Refactor buildTitleKeyword → buildTitleKeywords returning array.

frontend: trigger Navidrome startScan after download completes and wait
for scan to finish before running _createNdPlaylist, so newly downloaded
tracks are indexed and searchable when the playlist is built.

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

backend/novasonic-server.js

@@ -67,24 +67,25 @@ function artistFilterWord(name) {
   return best || '';
 }
 
-// Extract the most distinctive word from a track title to use as a title relevance filter.
-// Prevents fallback steps from downloading completely unrelated tracks.
-// Also preserves version qualifiers ("radio mix", "extended mix", "club mix", "vip mix") so
-// "Eclipse - Radio Mix" filters for "eclipse" AND "radio" to avoid downloading the plain version.
-function buildTitleKeyword(title) {
+// Extract distinctive words from a track title for case-insensitive yt-dlp title ~= (?i) filters.
+// Returns an array: [mainWord, optionalMixQualifier].
+// "Memories" → ["Memories"]  (matches "MEMORIES", "memories", etc.)
+// "Eclipse - Radio Mix" → ["Eclipse", "radio"]
+function buildTitleKeywords(title) {
   const VARIANT_WORDS = new Set(['sped','speedup','slowed','reverb','nightcore','karaoke','parody','remix','cover','acoustic','instrumental']);
   const STOPWORDS = new Set(['the','a','an','and','or','of','in','on','at','to','for','feat','ft','with']);
   const MIX_QUALIFIERS = ['radio', 'extended', 'club', 'vip', 'original', 'edit'];
   const lower = (title || '').toLowerCase();
-  const words = lower
+  // Keep original case so the word looks right in logs, case-insensitivity is handled by (?i) flag
+  const words = (title || '')
     .replace(/[^\w\s]/g, ' ')
     .split(/\s+/)
-    .filter(w => w.length >= 3 && !VARIANT_WORDS.has(w) && !STOPWORDS.has(w));
+    .filter(w => w.length >= 3 && !VARIANT_WORDS.has(w.toLowerCase()) && !STOPWORDS.has(w.toLowerCase()));
   const main = words.sort((a, b) => b.length - a.length)[0] || '';
-  // If the title has a mix qualifier AND "mix", include the qualifier word too
   const qualifier = lower.includes('mix') ? MIX_QUALIFIERS.find(q => lower.includes(q)) : null;
-  if (qualifier && qualifier !== main) return `${main} & title *= ${qualifier}`;
-  return main;
+  const result = main ? [main] : [];
+  if (qualifier && main.toLowerCase() !== qualifier) result.push(qualifier);
+  return result;
 }
 
 // Build yt-dlp --match-filter conditions to reject variant versions (speed up, slowed, remix…)
@@ -283,10 +284,11 @@ async function downloadTrack({ jobId, artist, albumArtist, title, album, year, t
 
   const uploaderWord   = artistFilterWord(mainArtist);
   const variantFilter  = buildVariantFilter(title);
-  const titleKeyword   = buildTitleKeyword(title);
+  const titleKws       = buildTitleKeywords(title);
   const uploaderPart   = uploaderWord  ? ` & artist *= ${uploaderWord}` : '';
   const variantPart    = variantFilter ? ` & ${variantFilter}` : '';
-  const titleKwPart    = titleKeyword  ? ` & title *= ${titleKeyword}` : '';
+  // ~= uses Python re.search; (?i) inline flag = case-insensitive substring match
+  const titleKwPart    = titleKws.length ? titleKws.map(k => ` & title ~= (?i)${k}`).join('') : '';
 
   // Build a --match-filter arg from active parts (duration, artist, variant, title keyword).
   // !is_live is always included. titleKw always included to avoid totally unrelated downloads.

src/ui.js

@@ -344,6 +344,18 @@ async function _pollAndCreatePlaylist(jobId, tracks, playlistName) {
     if (!job || job.status === 'done' || job.status === 'error') break;
   }
   if (S.jobs[jobId]?.status !== 'done') return;
+
+  // Trigger Navidrome library scan so newly downloaded files are indexed before searching
+  try {
+    await api('startScan', '');
+    toast('🔍 Navidrome scannt Bibliothek…');
+    for (let i = 0; i < 90; i++) {
+      await new Promise(r => setTimeout(r, 2000));
+      const st = await api('getScanStatus', '');
+      if (!st?.scanStatus?.scanning) break;
+    }
+  } catch { /* scan API unavailable — proceed anyway */ }
+
   await _createNdPlaylist(tracks, playlistName);
 }