curl https://api.zbdpay.com/api/v1/webhooks/subscriptions \
  -H "x-api-key: YOUR_API_KEY"

{
  "success": true,
  "message": "Subscriptions retrieved.",
  "data": {
    "subscriptions": [
      {
        "subscription_id": "sub_51a2",
        "url": "https://your-server.com/zbd/webhooks",
        "events": ["PAYMENTS.V1.PAYOUT.FAILED", "PAYMENTS.V1.PAYOUT.RETURNED"],
        "project_id": null,
        "status": "active"
      }
    ]
  },
  "error": null
}