feat: Research: NotebookLM — create audio overview of SOUL.md as podcast (#293)

Refs #293
Agent: groq

app.js

@@ -2172,6 +2172,23 @@ document.getElementById('audio-toggle').addEventListener('click', () => {
   }
 });
 
+// Podcast toggle
+const podcastAudio = new Audio('soul-podcast.mp3');
+const podcastToggle = document.getElementById('podcast-toggle');
+let podcastPlaying = false;
+
+podcastToggle.addEventListener('click', () => {
+  if (podcastPlaying) {
+    podcastAudio.pause();
+    podcastToggle.textContent = '🎧';
+    podcastPlaying = false;
+  } else {
+    podcastAudio.play().catch(() => {});
+    podcastToggle.textContent = '🔊';
+    podcastPlaying = true;
+  }
+});
+
 // === DEBUG MODE ===
 let debugMode = false;
 

index.html

@@ -33,6 +33,9 @@
     <button id="debug-toggle" class="chat-toggle-btn" aria-label="Toggle debug mode" style="background-color: var(--color-secondary); color: var(--color-bg); padding: 4px 8px; border-radius: 4px; font-size: 12px; cursor: pointer;">
       🔍
     </button>
+    <button id="podcast-toggle" class="chat-toggle-btn" aria-label="Toggle podcast" title="Toggle SOUL.md podcast" style="background-color: var(--color-accent); color: var(--color-bg); padding: 4px 8px; border-radius: 4px; font-size: 12px; cursor: pointer;">
+      🎧
+    </button>
     <button id="export-session" class="chat-toggle-btn" aria-label="Export session as markdown" title="Export session log as Markdown">
       📥
     </button>

style.css

@@ -62,6 +62,11 @@ canvas {
   background-color: var(--color-text-muted);
 }
 
+#podcast-toggle {
+  background-color: var(--color-accent);
+  color: var(--color-bg);
+}
+
 /* === DEBUG MODE === */
 #debug-toggle {
   margin-left: 8px;