feat(plugins): catalog images and purchase receipt uploads

Catalog items can store up to three photos; remote tenants attach a receipt on pending requests.

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

prisma/schema.prisma

@@ -343,6 +343,7 @@ model PluginCatalogItem {
   settingKey  String   @unique @map("setting_key") @db.VarChar(50)
   titleFa     String   @map("title_fa")
   description String?  @db.Text
+  images      Json?
   inStore     Boolean  @default(true) @map("in_store")
   createdAt   DateTime @default(now()) @map("created_at")
   updatedAt   DateTime @updatedAt @map("updated_at")
@@ -377,6 +378,7 @@ model PluginPurchaseRequest {
   status               PluginPurchaseStatus @default(pending)
   autoCutOnExpiry      Boolean?             @map("auto_cut_on_expiry")
   pluginSubscriptionId String?              @map("plugin_subscription_id")
+  receiptUrl           String?              @map("receipt_url")
   createdAt            DateTime             @default(now()) @map("created_at")
   updatedAt            DateTime             @updatedAt @map("updated_at")
   decidedAt            DateTime?            @map("decided_at")