curl -X GET "https://demo.api.vultlocal.com/api/v1/cards/OLIV0001" \
  -H "Authorization: Bearer olive_live_xxx"

{
  "card": {
    "serial": "OLIV0001",
    "mac_address": "AA:BB:CC:DD:EE:01",
    "type": "PARENT",
    "status": "ACTIVE",
    "subscriber_id": "sub_abc123",
    "subscriber_name": "John Doe",
    "linked_at": "2025-01-15T10:30:00Z",
    "created_at": "2025-01-01T00:00:00Z"
  }
}

{
  "card": {
    "serial": "OLIV0002",
    "mac_address": "AA:BB:CC:DD:EE:02",
    "type": "CHILD",
    "status": "ACTIVE",
    "subscriber_id": "sub_abc123",
    "parent_serial": "OLIV0001",
    "daily_limit": 5000000,
    "child_name": "Jane Doe",
    "linked_at": "2025-01-16T14:00:00Z"
  }
}

{
  "error": "Card not found",
  "code": "CARD_NOT_FOUND"
}