feat(store): add store sortOrder and swipeable package gallery

Enable HQ-controlled store list ordering and horizontal multi-image browsing on package detail.

Co-authored-by: Cursor <cursoragent@cursor.com>

server/dukang-api/prisma/schema.prisma

@@ -1277,6 +1277,8 @@ model Store {
   withdrawWhitelistEnabled Boolean @default(false) @map("withdraw_whitelist_enabled")
   /// 测试门店：不计结算 / HQ 可手动标记
   isTest          Boolean     @default(false) @map("is_test")
+  /// C 端 / 列表排序：数值越小越靠前
+  sortOrder       Int         @default(0) @map("sort_order")
   createdAt       DateTime    @default(now()) @map("created_at") @db.DateTime(3)
   updatedAt       DateTime    @updatedAt @map("updated_at") @db.DateTime(3)
 
@@ -1299,6 +1301,7 @@ model Store {
   @@index([partnerAccountId])
   @@index([auditStatus, createdAt])
   @@index([isTest])
+  @@index([sortOrder])
   @@map("store_store")
 }