Pause playback while transmitting and declare microphone use.

macOS refuses capture without a usage string, and queued remote audio was still handed to the speaker after push-to-talk began.

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend/dist/app.js

@@ -84,15 +84,5 @@ window.addEventListener("keyup", function (event) {
   }
 });
 
-window.addEventListener("blur", function () {
-  spaceHeld = false;
-  const app = api();
-  if (!app) {
-    return;
-  }
-  app.ReleaseButton();
-  app.ReleaseSpace();
-});
-
 setInterval(refresh, 100);
 refresh();