Register a new webhook endpoint

Registers an HTTPS endpoint to receive event notifications. The response includes a secret field — shown only once. Use it to verify HMAC-SHA256 signatures on deliveries.

Requires webhooks:manage scope. Requires Idempotency-Key header.

Delivery: POST to URL with JSON body, HMAC signature in X-Webhook-Signature header. Retries: 3 attempts (10s, 60s, 300s backoff). After 3 failures, webhook is deactivated.

curl -X POST "https://motivation-money.vercel.app/api/v1/webhooks" \  -H "Idempotency-Key: 7f3c4d2a-8b1e-4f6a-9c2d-1a5b8e3f7d4c" \  -H "Content-Type: application/json" \  -d '{    "url": "https://agent.acme.com/webhooks/payroll",    "events": [      "payroll.run.created"    ]  }'