curl --request GET \
  --url https://letterby.com/api/v4/lists \
  --header 'apiKey: <api-key>'

{
  "data": {
    "lists": [
      {
        "id": "<string>",
        "url": "<string>",
        "branding": true,
        "startFrom": 123,
        "mode": "<string>",
        "name": "<string>",
        "referrals": true,
        "color": "<string>",
        "title": "<string>",
        "desc": "<string>",
        "socialDescription": "<string>",
        "senderName": "<string>",
        "replyTo": "<string>",
        "sender": "<string>",
        "legal": "<string>",
        "createdAt": "2023-11-07T05:31:56Z",
        "updatedAt": "2023-11-07T05:31:56Z",
        "userId": "<string>",
        "domainId": "<string>",
        "defaultPageId": "<string>",
        "referralPageId": "<string>",
        "successPageId": "<string>",
        "icon": "<string>",
        "favicon": "<string>",
        "ogImage": "<string>",
        "listSettingsId": "<string>",
        "whitelistEmailId": "<string>",
        "templateId": "<string>",
        "themeId": "<string>",
        "columns": [
          "<string>"
        ],
        "customHeadCode": "<string>",
        "customBodyCode": "<string>",
        "googleAnalytics": "<string>",
        "plausibleAnalytics": "<string>"
      }
    ]
  }
}