List webhooks

{
  "items": [
    {
      "id": "550e8400-e29b-41d4-a716-446655440000",
      "user_id": "550e8400-e29b-41d4-a716-446655440000",
      "subscriptions": [
        "event_message",
        "event_action"
      ],
      "url": "https://example.com/webhook",
      "method": "POST",
      "label": "My Webhook",
      "description": "This is a description"
    }
  ],
  "page": 123,
  "size": 123,
  "has_more": true,
  "total": 123,
  "total_is_estimated": true
}