实现外部商品调价

backend/internal/modules/listing/service.go

@@ -29,6 +29,9 @@ var (
 	ErrUploaderNotFound         = errors.New("uploader not found")
 	ErrUploaderAmbiguous        = errors.New("uploader ambiguous")
 	ErrTooManyUploadItems       = errors.New("too many upload items")
+	ErrExternalListingRequired  = errors.New("external listing required")
+	ErrExternalAdjustment       = errors.New("invalid external listing adjustment")
+	ErrSaleRatioOutOfRange      = errors.New("sale ratio out of range")
 )
 
 type Service struct {