Merchant carts

const cart = await pepay.commerce.merchantCart.get({ customer_id: 'cust_123' });

const created = await pepay.commerce.merchantCart.create({ customer_id: 'cust_123' });

await pepay.commerce.merchantCart.addItem({
  customer_id: 'cust_123',
  productId: 'B08N5WRWNW',
  retailer: 'amazon',
  title: 'Echo (4th Gen)',
  price: 99.99,
  quantity: 1
});

await pepay.commerce.merchantCart.validate({ customer_id: 'cust_123' });

await pepay.commerce.merchantCart.totals({ customer_id: 'cust_123', zip_code: '94105' });

{
  "success": true,
  "data": {
    "merchantId": 123,
    "customerId": "cust_123",
    "items": [
      { "productId": "B08N5WRWNW", "quantity": 1 }
    ]
  }
}