List contact imports

curl -X GET 'https://www.unitpost.com/api/v1/contacts/imports' \
  -H 'Authorization: Bearer YOUR_API_KEY' \
  -H 'User-Agent: my-app/1.0'

{
  "object": "list",
  "has_more": false,
  "data": [
    {
      "object": "contact_import",
      "id": "id_123",
      "status": "pending",
      "total": 1,
      "imported": 0,
      "skipped": 0,
      "failed": 0,
      "invalid": [
        {
          "row": 0,
          "reason": "string"
        }
      ],
      "error": "string",
      "created_at": "2026-01-01T00:00:00.000Z",
      "updated_at": "2026-01-01T00:00:00.000Z"
    }
  ]
}