fix: restore controls after task completion

web/app.js

@@ -166,9 +166,16 @@ function updateModeUI() {
 
 async function setConversationMode(mode) {
     if (mode !== "voice" && mode !== "text") return;
+    const previousMode = conversationMode;
     conversationMode = mode;
     localStorage.setItem(MODE_KEY, mode);
     updateModeUI();
+    if (mode === "voice" && previousMode === "text") {
+        chatInput.blur();
+        window.setTimeout(() => {
+            document.querySelector(".workspace").scrollIntoView({ block: "start", behavior: "smooth" });
+        }, 0);
+    }
 
     if (!room || !room.localParticipant) return;
     sendModeMessage(mode);
@@ -314,9 +321,10 @@ function inferState() {
     userSpeaking = micLevel > 0.035;
     if (agentAudioLevel > 0.02) return "speaking";
     if (userSpeaking) return "listening";
-    // Not speaking, agent silent: stay in thinking until audio arrives,
-    // otherwise settle back to listening.
-    if (uiState === "thinking" || uiState === "speaking") return "thinking";
+    // Once agent audio ends, return to listening. The previous implementation
+    // converted speaking → thinking forever, leaving the UI apparently frozen.
+    if (uiState === "speaking") return "listening";
+    if (uiState === "thinking") return "thinking";
     return "listening";
 }