Why doesn’t SessionDataSet implement the IAsyncDisposable interface?

Currently, SessionDataSet implements the IDisposable interface. However, in its Dispose() method, the asynchronous Close() method is invoked synchronously.

Actual implementation:
```csharp
protected virtual void Dispose(bool disposing)
{
if (this.disposedValue)
return;
if (disposing)
{
try
{
//synchronous call
this.Close().Wait();
}
catch
{
}
}
this.disposedValue = true;
}
```

Proposed implementation:
```csharp
protected virtual Task DisposeAsync(bool disposing)
{
if (this.disposedValue)
return;
if (disposing)
{
try
{
//asynchronous call
await this.Close();
}
catch
{
}
}
this.disposedValue = true;
}
```

定位 SessionDataSet，並檢查其現有的 IDisposable 實作，尤其是 Dispose() 和非同步 Close() 進入點。確認該類別支援非同步釋放，且在不變更現有同步釋放行為的情況下等待 Close() 完成；該 issue 未提供測試或檔案路徑，因此應針對兩條釋放路徑檢查完成情況。

由索引模型根據 Issue 內容生成。