[BUG] worksheet addRows - undefined

## 🐛 Bug Report

Lib version: 4.4.0

## Steps To Reproduce

```javascript
import Excel from 'exceljs';
import { PassThrough } from 'stream';

const workbook = new Excel.stream.xlsx.WorkbookWriter({
stream: new PassThrough(),
useStyles: true,
useSharedStrings: true,
});

const worksheet = workbook.addWorksheet('My Sheet', {
pageSetup: { paperSize: 9, orientation: 'landscape' },
});

console.log({ addRows: worksheet.addRows });
```

## The expected behaviour:

addRows - must be function

## Possible solution (optional, but very helpful):

```javascript

```

The report centers on worksheet.addRows in the streaming WorkbookWriter setup shown in the reproduction. Start by tracing how workbook.addWorksheet creates the worksheet in the streaming API and compare the exposed worksheet methods. Done means addRows is available as a function for the shown setup and the reproduction no longer reports it as undefined.

Written by the indexing model from the issue text.