curl --request POST \
  --url https://api.example.com/trading/splits \
  --header 'Content-Type: application/json' \
  --data '
{
  "selections": [
    {
      "venue": "kalshi",
      "venueMarketOutcomeId": "<string>"
    }
  ],
  "side": "buy",
  "maxDollarAmount": 1
}
'

{
  "data": {
    "splits": [
      {
        "venue": "kalshi",
        "venueMarketOutcomeId": "<string>",
        "side": "buy",
        "price": 1,
        "size": 1,
        "signedOrder": null,
        "negRisk": true,
        "outcomeExternalIdentifier": "<string>"
      }
    ],
    "totalSize": 123,
    "totalCost": 123
  }
}