Create broadcast

curl --request POST \
  --url https://api.heyy.io/api/v2.0/{channelId}/broadcasts \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '{
  "name": "<string>",
  "workflowId": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "isScheduled": true,
  "scheduledAt": "2023-11-07T05:31:56Z",
  "isReoccurring": true,
  "recurrenceRules": [
    "<string>"
  ],
  "messageTemplateId": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "contacts": [
    {
      "firstName": "<string>",
      "lastName": "<string>",
      "email": "<string>",
      "phoneNumber": "<string>",
      "attributes": [
        {
          "externalId": "<string>",
          "value": "<string>"
        }
      ],
      "labels": [
        {
          "name": "<string>"
        }
      ]
    }
  ],
  "variables": [
    {
      "name": "<string>",
      "value": "<string>"
    }
  ]
}'

{
  "data": {
    "id": "<string>",
    "name": "<string>",
    "workflowId": "<string>",
    "isScheduled": true,
    "isReoccurring": true,
    "scheduledAt": "<string>",
    "recurrenceRules": "<any>",
    "variables": "<any>",
    "status": "<string>",
    "createdAt": "<string>",
    "updatedAt": "<string>"
  }
}