curl --request POST \
  --url https://app.voicery.ai/api/user/assistants/enable-conversation-ended-webhook \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '{
  "assistant_id": 123,
  "webhook_url": "https://yourdomain.com/webhook"
}'

{
  "message": "Conversation ended webhook enabled successfully",
  "data": []
}

{
  "message": "Assistant not found"
}

{
  "message": "The given data was invalid.",
  "errors": {
    "assistant_id": [
      "The assistant id field is required."
    ],
    "webhook_url": [
      "The webhook url field is required."
    ]
  }
}