feat(quality-owner): 增加优质号主、极品专区与无忧租号保险

- 支持保证金余额支付、在线支付开通及后台手动设置审计
- 新增极品专区发布权限、赔付方案与保险结算费率快照
- 优化首页、商品卡和个人中心的优质号主身份展示

backend/internal/modules/listing/service.go

@@ -33,6 +33,7 @@ var (
 	ErrExternalAdjustment       = errors.New("invalid external listing adjustment")
 	ErrSaleRatioOutOfRange      = errors.New("sale ratio out of range")
 	ErrDistributionSiteInvalid  = errors.New("invalid distribution site")
+	ErrPremiumOwnerRequired     = errors.New("premium listing requires quality owner")
 )
 
 type Service struct {
@@ -52,6 +53,8 @@ const (
 	defaultPublishCooldownMinutes = 5
 	maxExternalUploadItems        = 10
 	defaultUploadScreenshot       = "/api/listings/default-upload-screenshot?v=webp1"
+	CompensationPlanNormal        = "normal"
+	CompensationPlanInsurance     = "insurance"
 )
 
 type PublishCooldownError struct {