List outbound webhooks

Example response

{
  "webhooks": [
    {
      "id": "webhook_abc123",
      "name": "Production webhook",
      "url": "https://example.com/sequenzy/webhooks",
      "signingSecret": "whsec_...",
      "signingSecrets": [
        {
          "id": "sec_abc123",
          "prefix": "whsec_abcd12"
        }
      ]
    }
  ]
}