Prewarm upcoming queue streams

frontend/index.html

@@ -693,6 +693,7 @@
     <script src="piano.js"></script>
     <script src="setlist-import.js"></script>
     <script src="car-mode.js"></script>
+    <script src="prewarm-next.js"></script>
     <script src="app.js"></script>
   </body>
 </html>