Merge remote-tracking branch 'origin/develop' into feat/optimize

# Conflicts:
#	frontend/src/lib/errors.ts

frontend/src/components/ChatPanel/index.tsx

@@ -17,7 +17,7 @@ interface ChatPanelProps {
   currentScenario?: string;
   isProcessing?: boolean;
   isVADReady?: boolean;
-  vadError?: string;
+  vadError?: string | null;
   isMicOn?: boolean;
   isSpeaking?: boolean;
   onSendText?: (text: string) => void;