feat: 优化追问功能 - LLM智能生成 + 显示位置修复

- 修复 AuthLoader 组件中 router.push 在渲染期间调用的 React 警告
- 追问问题改为只在最新 AI 回复下方显示（修复多处显示问题）
- 新增 LLM 生成追问 API：POST /api/v1/apps/{id}/suggestions
- 前端调用 LLM API 生成智能追问，失败时降级到规则生成
- 登录页填入默认测试账号 kj-admin@govai.gov.cn

server/internal/handler/chat_llm.go

@@ -1737,3 +1737,100 @@ func (h *LLMChatHandler) generateConversationName(appID, userID, convID, userMes
 		DO UPDATE SET name = EXCLUDED.name, updated_at = now()`,
 		appID, userID, convID, name)
 }
+
+// GenerateSuggestions 生成追问建议（由 LLM 智能生成）
+func (h *LLMChatHandler) GenerateSuggestions(ctx context.Context, conversationID, appID string, messages []map[string]string) ([]string, error) {
+	if len(messages) == 0 {
+		return nil, nil
+	}
+
+	// 构建对话历史上下文
+	var historyBuilder strings.Builder
+	for i, msg := range messages {
+		role := "用户"
+		if msg["role"] == "assistant" {
+			role = "助手"
+		}
+		historyBuilder.WriteString(fmt.Sprintf("%d. %s：%s\n", i+1, role, msg["content"]))
+	}
+
+	systemPrompt := `你是一个智能政务问答助手。请根据对话历史，生成4个追问问题，帮助用户深入了解相关内容。
+
+要求：
+1. 问题必须与对话内容紧密相关
+2. 每个问题不超过20个字
+3. 问题要有深度，引导用户进一步思考
+4. 避免重复或过于宽泛的问题
+5. 直接输出问题，用换行分隔，不要编号，不要解释`
+
+	suggestReq := &llm.ChatRequest{
+		Model: "",
+		Messages: []llm.Message{
+			{Role: "system", Content: systemPrompt},
+			{Role: "user", Content: "对话历史：\n" + historyBuilder.String()},
+		},
+		Temperature: 0.7,
+		MaxTokens:   200,
+		Stream:      false,
+	}
+
+	// 获取激活的 provider
+	provider, defaultModel, err := h.getProviderWithModel(ctx)
+	if err != nil {
+		return nil, err
+	}
+	if defaultModel != "" {
+		suggestReq.Model = defaultModel
+	}
+
+	result, err := h.manager.Chat(ctx, provider, suggestReq)
+	if err != nil {
+		return nil, err
+	}
+
+	// 解析结果：按换行分割
+	suggestions := strings.Split(strings.TrimSpace(result.Content), "\n")
+	var validSuggestions []string
+	for _, s := range suggestions {
+		s = strings.TrimSpace(s)
+		// 过滤空行和过长的行
+		if len(s) > 0 && len([]rune(s)) <= 25 {
+			validSuggestions = append(validSuggestions, s)
+		}
+	}
+
+	// 最多返回4个
+	if len(validSuggestions) > 4 {
+		validSuggestions = validSuggestions[:4]
+	}
+
+	return validSuggestions, nil
+}
+
+// GetSuggestions HTTP handler：获取追问建议
+func (h *LLMChatHandler) GetSuggestions(w http.ResponseWriter, r *http.Request) {
+	ctx := r.Context()
+	appID := chi.URLParam(r, "id")
+	if appID == "" {
+		response.Error(w, http.StatusBadRequest, 40001, "缺少应用ID")
+		return
+	}
+
+	var req struct {
+		ConversationID string              `json:"conversation_id"`
+		Messages      []map[string]string `json:"messages"`
+	}
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		response.Error(w, http.StatusBadRequest, 40002, "请求格式错误")
+		return
+	}
+
+	suggestions, err := h.GenerateSuggestions(ctx, req.ConversationID, appID, req.Messages)
+	if err != nil {
+		log.Warn().Err(err).Msg("generate suggestions failed")
+		response.Error(w, http.StatusInternalServerError, 50001, "生成追问失败")
+		return
+	}
+
+	response.JSON(w, http.StatusOK, suggestions)
+}