Get first available dates for a brand

curl --request GET \
  --url https://api.letsway.com/v2/brands/{brandId}/first-available-session

{
  "scheduledDate": "2024-03-15",
  "sessions": [
    {
      "startDateTime": "2024-03-15T14:30:00Z",
      "experienceId": "exp-123",
      "hasPassed": false
    }
  ]
}