curl -X PUT 'https://api.opnform.com/open/forms/123/integrations/42' \
  -H 'Authorization: Bearer YOUR_PAT' \
  -H 'Content-Type: application/json' \
  -d '{
    "integration_id": "webhook",
    "status": "active",
    "data": {
      "webhook_url": "https://new-endpoint.com/opnform-hook",
      "webhook_secret": "whsec_newsecret123456789abcdef",
      "webhook_headers": {
        "X-API-Key": "new-api-key",
        "X-Custom-ID": "updated-value"
      }
    }
  }'

{
  "message": "Form Integration was updated.",
  "form_integration": {
    "id": 42,
    "form_id": 123,
    "integration_id": "webhook",
    "status": "active",
    "data": {
      "webhook_url": "https://new-endpoint.com/opnform-hook",
      "webhook_secret": "whsec_newsecret123456789abcdef",
      "webhook_headers": {
        "X-API-Key": "new-api-key",
        "X-Custom-ID": "updated-value"
      }
    }
  }
}

{
  "message": "The given data was invalid.",
  "errors": {
    "data.webhook_url": ["The webhook URL must use HTTPS."],
    "data.webhook_secret": ["The webhook secret must be at least 12 characters."],
    "data.webhook_headers": ["The 'Authorization' header cannot be customized for security reasons."]
  }
}