Enhance MobileCallPage functionality with camera view reset and chat transcript condition

- Update the effect to reset the view to "camera" when the call status is "idle" or "failed", improving user experience during call interruptions.
- Modify the rendering condition for the MobileCallTranscript to only display when inCall is true, ensuring chat messages are shown appropriately during active calls.

frontend/src/components/pages/MobileCallPage.tsx

@@ -300,7 +300,10 @@ export function MobileCallPage({ assistantId }: { assistantId: string }) {
   }, [startCall]);
 
   useEffect(() => {
-    if (status === "idle" || status === "failed") stopCamera();
+    if (status === "idle" || status === "failed") {
+      stopCamera();
+      setView("camera");
+    }
   }, [status, stopCamera]);
 
   const error = previewError || cameraError;
@@ -325,7 +328,7 @@ export function MobileCallPage({ assistantId }: { assistantId: string }) {
 
       <div className="pointer-events-none absolute inset-0 bg-gradient-to-b from-black/35 via-transparent to-black/65" />
 
-      {view === "chat" && <MobileCallTranscript messages={messages} />}
+      {view === "chat" && inCall && <MobileCallTranscript messages={messages} />}
 
       <NetworkQualityIndicator
         quality={networkQuality}