curl --request POST \
  --url https://api.onset.io/v1/milestones \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "title": "<string>",
  "status": "<string>",
  "slug": "<string>",
  "body": "<string>",
  "is_public": true,
  "project_id": "<string>",
  "label_ids": [
    "<string>"
  ],
  "attachments": [
    {
      "type": "FILE",
      "content": {
        "title": "<string>",
        "url": "<string>",
        "size": 123,
        "type": "<string>"
      },
      "id": "<string>"
    }
  ]
}
'

{
  "id": "<string>",
  "title": "<string>",
  "body": "<string>",
  "slug": "<string>",
  "status": "<string>",
  "stage": "<string>",
  "is_public": true,
  "upvote_count": 123,
  "project": {
    "id": "<string>",
    "name": "<string>",
    "slug": "<string>"
  },
  "labels": [
    {
      "id": "<string>",
      "name": "<string>",
      "slug": "<string>",
      "color": "<string>"
    }
  ],
  "attachments": [
    {
      "type": "FILE",
      "content": {
        "title": "<string>",
        "url": "<string>",
        "size": 123,
        "type": "<string>"
      },
      "id": "<string>"
    }
  ],
  "created_at": "2023-11-07T05:31:56Z",
  "updated_at": "2023-11-07T05:31:56Z"
}