Unexpected behavior of the CurrentBatchRowCount() method

In version 2.0.8 of the library, this method always returns 0, even though the dataset contains records. In earlier versions of the library, the RowCount property worked correctly and returned the actual number of records.

Code example:

```csharp
var count = dataset.CurrentBatchRowCount();
// variable count always contains 0

var list = new List(count);
while (await dataset.HasNextAsync())
{
var row = dataset.Next();
list.Add(new DataItem(row, false));
}
```

首先，使用提供的 C# 範例在函式庫版本 2.0.8 上重現問題，接著檢查 CurrentBatchRowCount() 的實作，並與先前的 RowCount 行為進行比較。完成條件是該方法回傳 dataset 的實際記錄數，且範例不再以 0 初始化清單。

由索引模型根據 Issue 內容生成。