feat：语音对话优化

frontend/src/App.tsx

@@ -306,17 +306,9 @@ function AppContent() {
             {isAudioPlaying && config.ttsEnabled && (
               <div className="video-indicator video-indicator--audio">{tr("video.playing")}</div>
             )}
-            {isConnected && !isVADReady && !vadError && (
-              <div className="video-indicator video-indicator--loading">{tr("video.initVad")}</div>
-            )}
             {vadError && (
               <div className="video-indicator video-indicator--error">⚠️ {vadError}</div>
             )}
-            {isProcessing && (
-              <div className="video-overlay">
-                <div className="video-overlay__spinner" />
-              </div>
-            )}
             {!isConnected && !stream && (
               <div className="video-placeholder">
                 <svg className="video-placeholder__icon" width="48" height="48" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="1.2" strokeLinecap="round" strokeLinejoin="round">
@@ -473,6 +465,9 @@ function AppContent() {
               messages={messages}
               currentReply={currentReply}
               connectionStatus={connectionStatus}
+              isProcessing={isProcessing}
+              isVADReady={isVADReady}
+              vadError={vadError}
               isMicOn={isMicOn}
               isSpeaking={isSpeaking}
               onSendText={sendTextMessage}