Fill Updates

{
  "method": "subscribe",
  "subscription": {
    "type": "userFills",
    "user": "0x1111111111111111111111111111111111111111"
  }
}

{
  "channel": "userFills",
  "data": {
    "user": "0x1111111111111111111111111111111111111111",
    "isSnapshot": false,
    "fills": [
      {
        "coin": "BTC",
        "marketAssetId": "00020000",
        "px": "50000.00",
        "sz": "0.1",
        "side": "B",
        "time": 1701234567890,
        "startPosition": "0",
        "dir": "Open Long",
        "closedPnl": "0",
        "hash": "0x1234...",
        "orderId": "0x1234567890abcdef1234567890abcdef",
        "crossed": true,
        "fee": "2.50",
        "tid": 67890,
        "feeToken": "USDC"
      }
    ]
  }
}