Fix audio on Android Chrome / Mi Browser

- audioCtx.resume() explizit aufrufen (Android suspendiert AudioContext)
- ws:// vs wss:// dynamisch je nach Seitenprotokoll
- Button zeigt "Verbinde…" bis WebSocket offen ist
- onclose Handler setzt Button zurück auf "Ton an"

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

app/templates/live.html

@@ -206,21 +206,35 @@
       btn.textContent = "🔇 Ton an";
       audioOn = false;
     } else {
+      btn.textContent = "⏳ Verbinde…";
       startAudio();
-      btn.textContent = "🔊 Ton aus";
       audioOn = true;
     }
   }
 
   function startAudio() {
     audioCtx = new (window.AudioContext || window.webkitAudioContext)({ sampleRate: SAMPLE_RATE });
-    nextPlayTime = audioCtx.currentTime;
 
-    const wsUrl = `ws://${location.host}/audio-ws`;
+    // Android/Chrome suspendiert AudioContext standardmäßig → explizit resumem
+    audioCtx.resume().then(() => {
+      nextPlayTime = audioCtx.currentTime;
+      connectWs();
+    });
+  }
+
+  function connectWs() {
+    // ws:// oder wss:// je nach Seitenprotokoll
+    const proto = location.protocol === "https:" ? "wss" : "ws";
+    const wsUrl = `${proto}://${location.host}/audio-ws`;
     audioWs = new WebSocket(wsUrl);
     audioWs.binaryType = "arraybuffer";
 
+    audioWs.onopen = () => {
+      document.getElementById("audio-btn").textContent = "🔊 Ton aus";
+    };
+
     audioWs.onmessage = (event) => {
+      if (!audioCtx) return;
       const pcm16 = new Int16Array(event.data);
       const buffer = audioCtx.createBuffer(1, pcm16.length, SAMPLE_RATE);
       const data = buffer.getChannelData(0);
@@ -231,13 +245,16 @@
       source.buffer = buffer;
       source.connect(audioCtx.destination);
       const now = audioCtx.currentTime;
-      // Kleine Puffer-Queue (~40ms) damit keine Lücken entstehen
       if (nextPlayTime < now) nextPlayTime = now + 0.04;
       source.start(nextPlayTime);
       nextPlayTime += buffer.duration;
     };
 
     audioWs.onerror = () => stopAudio();
+    audioWs.onclose = () => {
+      if (audioOn) stopAudio();
+      document.getElementById("audio-btn").textContent = "🔇 Ton an";
+    };
   }
 
   function stopAudio() {