Get Interest-free/Fixed installments configuration

This endpoint retrieves the current Installments-free/Fixed installments for an account, if there is no custom configuration, it creates a new one for the account with the default values.

Endpoint: GET /api/cards/msi-configuration

Request:

curl -X GET https://api.ecartpay.com/api/cards/msi-configuration \
  -H "Authorization: eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9..."

Response:

{
  "gateway": "ecartpay",
  "brands": ["visa", "mastercard", "amex"],
  "installments": [3, 6, 9, 12, 18],
  "institutions": [
    "banamex", "bancomer", "santander", "scotiabank", 
    "hsbc", "banorte", "american express", "liverpool"....
  ],
  "is_active": true,
  "commissions": [
    {
      "installments": 3,
      "rate": 3.5,
      "minimum_amount": 300,
      "currency": "MXN",
      "is_active": true,
      "fixed_installments": false
    },
    {
      "installments": 6,
      "rate": 5.5,
      "minimum_amount": 600,
      "currency": "MXN",
      "is_active": true,
      "fixed_installments": false
    },
    {
      "installments": 9,
      "rate": 8.5,
      "minimum_amount": 900,
      "currency": "MXN",
      "is_active": false,
      "fixed_installments": false
    },
    {
      "installments": 12,
      "rate": 11.5,
      "minimum_amount": 1200,
      "currency": "MXN",
      "is_active": true,
      "fixed_installments": true
    },
    {
      "installments": 18,
      "rate": 15,
      "minimum_amount": 1800,
      "currency": "MXN",
      "is_active": false,
      "fixed_installments": false
    }
  ],
  "amex_rates": {
    "3": 3.25,
    "6": 6.25,
    "9": 8.25,
    "12": 10.25,
    "15": 13.25,
    "18": 15.25,
    "21": 17.25,
		"24": 19.25
  },
  "amex_fixed_installments": false,
  ]
}