feat(player): add explicit detection, inline audio preview, seeking scrubber, and stream endpoint

app/templates/index.html

@@ -107,6 +107,30 @@
     </footer>
   </div>
 
+  <!-- Floating Audio Preview Player -->
+  <div id="audioPlayerBar" class="audio-player-bar" style="display: none;">
+    <div class="player-track-info">
+      <img id="playerCover" class="player-cover" src="" alt="Cover" />
+      <div class="player-meta">
+        <div class="player-title-row">
+          <span id="playerTitle" class="player-title"></span>
+          <span id="playerExplicitBadge" class="badge"></span>
+        </div>
+        <span id="playerArtist" class="player-artist"></span>
+      </div>
+    </div>
+    
+    <div class="player-controls-container">
+      <audio id="globalAudioPlayer" controls preload="metadata"></audio>
+    </div>
+
+    <div class="player-actions">
+      <button id="playerImportBtn" class="btn-sm btn-import">📥 В Navidrome</button>
+      <button id="playerDownloadBtn" class="btn-sm btn-direct-dl">💾 Скачать</button>
+      <button id="playerCloseBtn" class="btn-player-close" title="Закрыть плеер">&times;</button>
+    </div>
+  </div>
+
   <script src="static/app.js"></script>
 </body>
 </html>