feat(adminuser): 优化用户管理筛选并展示筛选人数

- 免押额度与号主类型改为下拉筛选，支持有/无和优质/普通
- 新增用户成长等级筛选
- 列表上方固定展示筛选结果人数，补充组合筛选测试

backend/internal/modules/adminuser/handler.go

@@ -42,6 +42,9 @@ func (h *Handler) List(c *gin.Context) {
 		Status:              strings.TrimSpace(c.Query("status")),
 		HasDepositFreeQuota: parseBoolQuery(c.Query("has_deposit_free_quota")),
 		QualityOwnerOnly:    parseBoolQuery(c.Query("quality_owner_only")),
+		DepositFreeQuota:    normalizeEnumQuery(c.Query("deposit_free_quota"), "has", "none"),
+		OwnerType:           normalizeEnumQuery(c.Query("owner_type"), "quality", "normal"),
+		GrowthLevel:         strings.TrimSpace(c.Query("growth_level")),
 	}
 	result, err := h.service.List(c.Request.Context(), page, pageSize, query)
 	if err != nil {
@@ -60,6 +63,16 @@ func parseBoolQuery(value string) bool {
 	}
 }
 
+func normalizeEnumQuery(value string, allowed ...string) string {
+	value = strings.ToLower(strings.TrimSpace(value))
+	for _, item := range allowed {
+		if value == item {
+			return value
+		}
+	}
+	return ""
+}
+
 func (h *Handler) Freeze(c *gin.Context) {
 	adminID, ok := currentAdminID(c)
 	if !ok {