결제 기능

const session = await client.checkoutSessions.create({
  product_cart: [
    { product_id: 'prod_abc', quantity: 1 }
  ],
  discount_code: 'WELCOME20', // Pre-apply a code
  feature_flags: {
    allow_discount_code: true // Show discount input field
  },
  return_url: 'https://yoursite.com/return'
});

const session = await client.checkoutSessions.create({
  product_collection_id: 'pdc_abc123',
  product_cart: [], // Required: pass an empty array for collection checkout
  return_url: 'https://yoursite.com/return'
});

const session = await client.checkoutSessions.create({
  product_cart: [
    { product_id: 'prod_abc', quantity: 1 }
  ],
  customer: {
    email: 'customer@example.com',
    name: 'Jane Doe'
  },
  billing_currency: 'EUR', // Set specific currency
  discount_code: 'PROMO10',
  feature_flags: {
    allow_discount_code: true
  },
  return_url: 'https://yoursite.com/return',
  metadata: {
    order_ref: 'ORD-12345'
  }
});