chore：支持换一换按钮应用

pages_tool/ai-chat/ai-chat-message.vue

@@ -1779,6 +1779,8 @@ export default {
 
       // 3. 插入欢迎语（再次检查是否仍是全新会话）
       if (!this.currentConversationId && this.messages.length === 0) {
+        // PR-WELCOME-QUICK-BATCH: 所有快捷问题先存起来, 前端每 4 个一批轮播
+        const allQuickQuestions = this.normalizeQuickQuestions(welcomeInfo && welcomeInfo.quick_questions)
         const welcomeMsg = {
           id: ++this.messageId,
           role: 'ai',
@@ -1789,7 +1791,10 @@ export default {
           // PR-WELCOME-QUICK-CHIPS (2026-09-19): 欢迎语配套快捷问题 (chips)
           //   后端可存 string[] 或 {id,text}[] ,前端统一归一化为 string[]
           //   message.quickQuestions 数组非空 → 模板渲染 chips;点击调 onQuickQuestionClick
-          quickQuestions: this.normalizeQuickQuestions(welcomeInfo && welcomeInfo.quick_questions),
+          // PR-WELCOME-QUICK-BATCH: 每 4 个一批展示, 点击换一换循环切换
+          quickQuestions: (allQuickQuestions || []).slice(0, 4),
+          allQuickQuestions: allQuickQuestions || [],
+          _qqBatchIndex: 0,
           // PR-WELCOME-HIDE-AFTER-SEND: 标记这是欢迎语消息, 发送第一条用户消息后永久隐藏
           isWelcome: true
         }
@@ -3764,13 +3769,23 @@ _handleStreamError(msg) {
       } catch (e) { /* noop */ }
     },
 
-    // 欢迎语"换一换": 移除当前欢迎语并重新加载(刷新快捷问题)
+    // 欢迎语"换一换": 快捷问题每 4 个一批, 点击后切换到下一批, 末尾循环回第一批
     onAiActionRefreshWelcome(message) {
       try {
-        const idx = this.messages.findIndex(m => m && m.id === message.id)
-        if (idx !== -1) this.messages.splice(idx, 1)
-        this._welcomeLoading = false
-        this._loadWelcomeMessage()
+        const all = message.allQuickQuestions || []
+        if (!all.length) {
+          uni.showToast({ title: '暂无更多问题', icon: 'none' })
+          return
+        }
+        const batchSize = 4
+        const total = all.length
+        const batchCount = Math.ceil(total / batchSize) || 1
+        const current = message._qqBatchIndex || 0
+        const next = (current + 1) % batchCount
+        const start = next * batchSize
+        const end = Math.min(start + batchSize, total)
+        this.$set(message, '_qqBatchIndex', next)
+        this.$set(message, 'quickQuestions', all.slice(start, end))
       } catch (e) { /* noop */ }
     },