List accounts

curl --request GET \
  --url https://sandbox-api.billingrails.com/v1/accounts \
  --header 'Authorization: Bearer <token>'

{
  "accounts": [
    {
      "object": "account",
      "id": "acc_IhMUl3rrZ3",
      "created_at": "2025-02-14T17:33:40.843Z",
      "external_id": "test_account",
      "type": "individual",
      "name": "John Doe",
      "email": "john@test.xyz",
      "default_currency": "NGN",
      "country": "NG",
      "invoice_settings": {
        "number_prefix": "INV",
        "grace_period_days": 0,
        "net_term_days": 30
      },
      "preferred_locale": "en",
      "metadata": null
    }
  ]
}