Creates a communications stage

curl --request POST \
  --url https://api.rootly.com/v1/communications/stages \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/vnd.api+json' \
  --data '
{
  "data": {
    "type": "communications_stages",
    "attributes": {
      "name": "<string>",
      "description": "<string>",
      "position": 123
    }
  }
}
'

{
  "data": {
    "id": "c134470c-2d38-4907-8ce8-28ae0301c905",
    "type": "communications_stages",
    "attributes": {
      "name": "Investigation Started",
      "slug": "investigation-started",
      "description": "Stage when investigation begins",
      "position": 11,
      "created_at": "2026-01-08T15:51:01.023-08:00",
      "updated_at": "2026-01-08T15:51:01.023-08:00"
    }
  }
}