Create webhook

curl -X POST 'https://api.sndr.sh/v1/webhooks' \
  -H "Authorization: Bearer $SNDR_API_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
    "url":    "https://your-app.com/webhooks/sndr",
    "events": ["email.delivered", "email.bounced", "email.failed"]
  }'

{
  "id":              "wh_2a7d4e9c-6b1",
  "organization_id": "org_8d41c7a2-3f6",
  "url":             "https://your-app.com/webhooks/sndr",
  "events":          ["email.delivered", "email.bounced", "email.failed"],
  "secret_prefix":   "whsec_Xk9pQ2",
  "active":          true,
  "created_at":      "2026-06-01T12:00:00Z",
  "secret":          "Xk9pQ2vLr8TzW4mN1bYcE7hJ0aSdFgUi"
}