Get merchant info

Example response

{
  "payload": {
    "id": "123e4567-e89b-12d3-a456-426614174000",
    "preferredName": "Merchant 1",
    "internalName": "Merchant 1",
    "billingContact": {
      "email": "billing@merchant.com",
      "phone": "+1-555-123-4567"
    },
    "logo": "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAA..."
  }
}