curl --request GET \
  --url https://api.ledger.so/v1/cards/{cardId} \
  --header 'Api-Key: <api-key>'

{
  "id": "<string>",
  "agentId": "<string>",
  "userId": "<string>",
  "type": "single",
  "purpose": "<string>",
  "status": "active",
  "last4": "<string>",
  "createdAt": 123,
  "credentialExposure": "never",
  "expirationMonth": "<string>",
  "expirationYear": "<string>",
  "limits": {
    "perAuth": 123,
    "perDay": 123,
    "perMonth": 123
  },
  "merchantHint": "<string>",
  "ttlDays": 123
}