fix(frontend): 修复 speechSynthesis.cancel() 未守卫导致的页面崩溃

frontend/web/src/hooks/useSpeechSynthesis.ts

@@ -131,13 +131,13 @@ export function useSpeechSynthesis(): UseSpeechSynthesisReturn {
 
   // Chrome bug 规避：定期 resume 避免长时间不调用后暂停
   useEffect(() => {
-    if (isSpeaking && !isPaused) {
-      resumeIntervalRef.current = setInterval(() => {
-        if (window.speechSynthesis.speaking && window.speechSynthesis.paused) {
-          window.speechSynthesis.resume();
-        }
-      }, 5000);
-    }
+    if (!isSupported || !isSpeaking || isPaused) return;
+
+    resumeIntervalRef.current = setInterval(() => {
+      if (window.speechSynthesis.speaking && window.speechSynthesis.paused) {
+        window.speechSynthesis.resume();
+      }
+    }, 5000);
 
     return () => {
       if (resumeIntervalRef.current) {
@@ -145,7 +145,7 @@ export function useSpeechSynthesis(): UseSpeechSynthesisReturn {
         resumeIntervalRef.current = null;
       }
     };
-  }, [isSpeaking, isPaused]);
+  }, [isSupported, isSpeaking, isPaused]);
 
   /** 朗读下一段 */
   const speakNextChunk = useCallback(() => {
@@ -221,29 +221,37 @@ export function useSpeechSynthesis(): UseSpeechSynthesisReturn {
 
   /** 停止朗读 */
   const stop = useCallback(() => {
-    window.speechSynthesis.cancel();
+    if (!isSupported) {
+      console.warn('[useSpeechSynthesis] stop: speechSynthesis not supported');
+      return;
+    }
+    if (utteranceRef.current) {
+      window.speechSynthesis.cancel();
+    }
     setIsSpeaking(false);
     setIsPaused(false);
     utteranceRef.current = null;
     chunksRef.current = [];
     chunkIndexRef.current = 0;
-  }, []);
+  }, [isSupported]);
 
   /** 暂停 */
   const pause = useCallback(() => {
+    if (!isSupported) return;
     if (isSpeaking && !isPaused) {
       window.speechSynthesis.pause();
       setIsPaused(true);
     }
-  }, [isSpeaking, isPaused]);
+  }, [isSupported, isSpeaking, isPaused]);
 
   /** 恢复 */
   const resume = useCallback(() => {
+    if (!isSupported) return;
     if (isPaused) {
       window.speechSynthesis.resume();
       setIsPaused(false);
     }
-  }, [isPaused]);
+  }, [isSupported, isPaused]);
 
   /** 设置语音 */
   const setVoice = useCallback((voice: SpeechSynthesisVoice) => {
@@ -253,12 +261,14 @@ export function useSpeechSynthesis(): UseSpeechSynthesisReturn {
   // 组件卸载时停止
   useEffect(() => {
     return () => {
-      window.speechSynthesis.cancel();
+      if (isSupported && utteranceRef.current) {
+        window.speechSynthesis.cancel();
+      }
       if (resumeIntervalRef.current) {
         clearInterval(resumeIntervalRef.current);
       }
     };
-  }, []);
+  }, [isSupported]);
 
   return {
     isSpeaking,