feat: 添加消息卡片功能方法

- copyMessageContent: 复制消息内容到剪贴板
- playMessageTts: 播放故事 TTS 音频
- toggleMessageCollapse: 添加展开/收起埋点

mini-program/src/pages/main/ScriptView.vue

@@ -444,6 +444,37 @@ const toggleMessageCollapse = (message) => {
     [message.id]: !isMessageCollapsed(message)
   }
   nextTick(measureResultViewport)
+  analytics.track('script_message_collapse_toggle', {
+    message_id: message?.id || '',
+    collapsed: collapsedMessageIds.value[message.id]
+  }, { eventType: 'script', pagePath })
+}
+
+const copyMessageContent = (message) => {
+  const content = String(message?.content || '')
+  if (!content.trim()) {
+    uni.showToast({ title: '暂无可复制内容', icon: 'none' })
+    return
+  }
+  uni.setClipboardData({
+    data: content,
+    success: () => {
+      uni.showToast({ title: '已复制', icon: 'success' })
+    }
+  })
+  analytics.track('script_message_copy_click', {
+    message_id: message?.id || '',
+    content_length: content.length
+  }, { eventType: 'script', pagePath })
+}
+
+const playMessageTts = (message) => {
+  const scriptId = currentResult.value?.id || ''
+  ttsPlayer.playSource(scriptId)
+  analytics.track('script_message_tts_click', {
+    message_id: message?.id || '',
+    script_id: scriptId
+  }, { eventType: 'script', pagePath })
 }
 
 const visibleStreamContent = computed(() => streamWriter.visibleText.value)