fix(s2s-text): 9 review bugs - text stream, loading, history, unmount safety

Backend (VoiceGatewayService):
- [P0 Bug-1] handleAssistantChunk/Final: text mode must never apply blockUpstreamAudio
  gate to text events (blockUpstreamAudio is for audio frames only). Non-KB text
  queries now correctly stream subtitle back to client.
- [P0 Bug-3] sendUpstreamChatTextQuery: when upstream not ready, send
  assistant_pending:false before error so client loading spinner can clear.
- [P1 Bug-6] handleUserPartial/handleUserFinal: early-return if textMode, guard
  against spurious ASR echoes from S2S.

Frontend (ChatPanel S2S effect):
- [P0 Bug-2] Connection success now clears error; added cancelled flag to all
  async setState paths to prevent state reversal on unmount.
- [P1 Bug-4] onAssistantPending: (false) always clears isLoading; (true) only
  sets isLoading if not already streaming (streamingId drives UI, pending is
  advisory).
- [P1 Bug-5] S2S mode loads session history via getSessionHistory (was Coze-only).
- [P2 Bug-8] When s2sService ref is null, also remove the placeholder assistant
  bubble to avoid stale empty bubble in chat.
- [P2 Bug-9] All callbacks guard on cancelled flag to prevent React setState
  warnings after unmount (cleanup triggers svc.disconnect which emits
  'disconnected' state).

Verification: mvn test VoiceGatewaySmokeTest 20/20 pass, no voice regression.

java-server/src/main/java/com/bigwo/javaserver/service/VoiceGatewayService.java

@@ -322,6 +322,9 @@ public class VoiceGatewayService {
     private void sendUpstreamChatTextQuery(VoiceSessionState state, String text) {
         if (state.upstream == null || !state.upstreamReady) {
             log.warn("[VoiceGateway][text-mode] upstream not ready, drop text session={}", state.sessionId);
+            // Reset pending state so client loading indicator can clear
+            state.awaitingUpstreamReply = false;
+            sendJson(state, Map.of("type", "assistant_pending", "active", Boolean.FALSE));
             sendJson(state, Map.of("type", "error", "error", "语音服务尚未就绪，请稍后重试"));
             return;
         }
@@ -502,6 +505,10 @@ public class VoiceGatewayService {
     }
 
     private void handleUserPartial(VoiceSessionState state, JsonNode payload) {
+        if (state.textMode) {
+            // Text mode: S2S should not emit ASR events; guard against spurious echoes.
+            return;
+        }
         String text = extractUserText(payload, state.sessionId);
         if (!StringUtils.hasText(text)) {
             return;
@@ -590,6 +597,9 @@ public class VoiceGatewayService {
     }
 
     private void handleUserFinal(VoiceSessionState state, JsonNode payload, int eventCode) {
+        if (state.textMode) {
+            return;
+        }
         String rawFinalText = extractUserText(payload, state.sessionId);
         String normalizedFinal = StringUtils.hasText(rawFinalText) ? knowledgeQueryResolver.normalizeKnowledgeText(rawFinalText, true) : "";
         String finalText = StringUtils.hasText(normalizedFinal) ? normalizedFinal : state.latestUserText;
@@ -666,7 +676,11 @@ public class VoiceGatewayService {
     private void handleAssistantFinal(VoiceSessionState state, JsonNode payload) {
         boolean isLocalChatTTSActive = state.isSendingChatTTSText && state.chatTTSUntil > System.currentTimeMillis();
         boolean isSuppressing = state.suppressUpstreamUntil > System.currentTimeMillis();
-        if (isLocalChatTTSActive || state.blockUpstreamAudio || isSuppressing) {
+        // Text mode: blockUpstreamAudio only gates audio frames, never text finals — always deliver 351 text
+        boolean shouldDropFinal = state.textMode
+                ? (isLocalChatTTSActive || isSuppressing)
+                : (isLocalChatTTSActive || state.blockUpstreamAudio || isSuppressing);
+        if (shouldDropFinal) {
             state.clearAssistantBuffer();
             return;
         }
@@ -744,7 +758,8 @@ public class VoiceGatewayService {
         if (isSuppressing && !"external_rag".equals(state.currentTtsType)) {
             return;
         }
-        if (state.blockUpstreamAudio && !"external_rag".equals(state.currentTtsType)) {
+        // Text mode: blockUpstreamAudio only gates audio frames, never text — always pass text through
+        if (!state.textMode && state.blockUpstreamAudio && !"external_rag".equals(state.currentTtsType)) {
             return;
         }
         String chunk = extractRawText(payload);

test2/client/src/components/ChatPanel.jsx

@@ -23,48 +23,86 @@ export default function ChatPanel({ sessionId, voiceSubtitles, settings, onBack,
     if (!useS2S || !sessionId) {
       return undefined;
     }
+    // Track mount status to avoid setState after unmount (Bug-9)
+    let cancelled = false;
+    const safeSet = (fn) => { if (!cancelled) fn(); };
+
     const svc = new NativeVoiceService();
     s2sServiceRef.current = svc;
 
+    // Load history messages for S2S mode too (Bug-5)
+    (async () => {
+      try {
+        const historyData = await getSessionHistory(sessionId, 20);
+        if (cancelled) return;
+        if (historyData?.messages?.length > 0) {
+          const historyMsgs = historyData.messages.map((m, i) => ({
+            id: `history-${i}`,
+            role: m.role,
+            content: m.content,
+            fromVoice: true,
+          }));
+          setMessages((prev) => (prev.length === 0 ? historyMsgs : prev));
+        }
+      } catch (e) {
+        console.warn('[ChatPanel][S2S] history load failed:', e.message);
+      }
+    })();
+
     svc.on('onSubtitle', (data) => {
-      if (!data || !data.role) return;
+      if (!data || !data.role || cancelled) return;
       if (data.role === 'user') {
-        // User subtitle is just an echo of what we already inserted; skip
         return;
       }
-      // assistant subtitle: streaming chunks (isFinal=false) or final (isFinal=true)
       const assistantId = s2sStreamingIdRef.current;
       if (!assistantId) return;
-      setMessages((prev) => prev.map((m) => (
+      safeSet(() => {
-        m.id === assistantId
+        setMessages((prev) => prev.map((m) => (
-          ? { ...m, content: data.text || '', streaming: !data.isFinal }
+          m.id === assistantId
-          : m
+            ? { ...m, content: data.text || '', streaming: !data.isFinal }
-      )));
+            : m
+        )));
+      });
       if (data.isFinal) {
-        setIsLoading(false);
+        safeSet(() => {
-        setStreamingId(null);
+          setIsLoading(false);
+          setStreamingId(null);
+        });
         s2sStreamingIdRef.current = null;
         inputRef.current?.focus();
       }
     });
+    // Bug-4: onAssistantPending(false) should also clear streaming state consistently;
+    // do NOT override isLoading when pending=true if we're already streaming (streamingId drives UI).
     svc.on('onAssistantPending', (active) => {
-      setIsLoading(!!active);
+      if (cancelled) return;
+      if (!active) {
+        safeSet(() => setIsLoading(false));
+      } else if (!s2sStreamingIdRef.current) {
+        safeSet(() => setIsLoading(true));
+      }
     });
     svc.on('onError', (err) => {
-      setError(err?.message || 'S2S 文字模式错误');
+      if (cancelled) return;
-      setIsLoading(false);
+      safeSet(() => {
-      setStreamingId(null);
+        setError(err?.message || 'S2S 文字模式错误');
+        setIsLoading(false);
+        setStreamingId(null);
+      });
       s2sStreamingIdRef.current = null;
     });
     svc.on('onIdleTimeout', () => {
-      setError('S2S 连接超时，已断开。请刷新页面重连');
+      if (cancelled) return;
-      setIsInitialized(false);
+      safeSet(() => {
-    });
+        setError('S2S 连接超时，已断开。请刷新页面重连');
-    svc.on('onConnectionStateChange', (state) => {
-      if (state === 'connected') {
-        // wait for onReady (handled via promise in connect)
-      } else if (state === 'disconnected' || state === 'error') {
         setIsInitialized(false);
+      });
+    });
+    // Bug-9: only treat as disconnect if we haven't initiated cleanup
+    svc.on('onConnectionStateChange', (state) => {
+      if (cancelled) return;
+      if (state === 'disconnected' || state === 'error') {
+        safeSet(() => setIsInitialized(false));
       }
     });
 
@@ -80,13 +118,16 @@ export default function ChatPanel({ sessionId, voiceSubtitles, settings, onBack,
           playAudioReply: !!playAudioReply,
           disableGreeting: true,
         });
-        setIsInitialized(true);
+        if (cancelled) return;
+        safeSet(() => { setIsInitialized(true); setError(null); });
       } catch (e) {
-        setError(`S2S 连接失败：${e?.message || e}`);
+        if (cancelled) return;
+        safeSet(() => setError(`S2S 连接失败：${e?.message || e}`));
       }
     })();
 
     return () => {
+      cancelled = true;
       svc.disconnect().catch(() => {});
       s2sServiceRef.current = null;
       s2sStreamingIdRef.current = null;
@@ -208,6 +249,8 @@ export default function ChatPanel({ sessionId, voiceSubtitles, settings, onBack,
         setError('S2S 服务未就绪');
         setIsLoading(false);
         setStreamingId(null);
+        // Bug-8: remove the empty placeholder assistant bubble we just inserted
+        setMessages((prev) => prev.filter((m) => m.id !== assistantId));
         return;
       }
       s2sStreamingIdRef.current = assistantId;