Could we provide a potentially larger InternalParquetRecordWriter.getDataSize

The following code currently has getDataSize as an estimated value. The Iceberg rolling file write operation relies on this method, which may result in writing files that are much smaller than expected.
```JAVA
/**
* @return the total size of data written to the file and buffered in memory
*/
public long getDataSize() {
return lastRowGroupEndPos + columnStore.getBufferedSize();
}
```

Could we provide a potentially larger getDataSize? I can't think of any downsides at the moment.

### Component(s)

_No response_

定位 InternalParquetRecordWriter.getDataSize，并追踪 Iceberg 的滚动文件写入操作如何使用其值。将报告的大小与实际写入和缓冲的数据进行比较，然后定义并测试一个更大且安全的大小估算值，以防止文件大小意外过小。

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