curl -X POST "https://api.arkhq.io/v1/tenants/cm6abc123def456/credentials" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "production-smtp",
    "type": "smtp"
  }'

{
  "success": true,
  "data": {
    "id": 123,
    "name": "production-smtp",
    "type": "smtp",
    "hold": false,
    "key": "cred_a1b2c3d4e5f6g7h8i9j0...",
    "smtpUsername": "cm6abc123def456/cred_a1b2c3d4e5f6g7h8i9j0...",
    "lastUsedAt": null,
    "createdAt": "2026-02-03T10:30:00Z",
    "updatedAt": "2026-02-03T10:30:00Z"
  },
  "meta": {
    "requestId": "req_abc123xyz"
  }
}