Managing ownership in VectorSchemaRoot#addVector, recent changes miss the main fault.

A recent change in VectorSchemaRoot#addVector provided a simple improvement, but completely misses a major shortcoming of this routine and, almost certainly, others like it. Based on the interest in that issue (#301), this issue might be of interest to @axreldable and @jbonofre.

One cannot change the `FieldVector`s belonging to `VectorSchemaRoot`s by simply rearranging the elements of their `List`s without considering the ownership of their underlying buffers. This can cause various problems, particularly when `VectorSchemaRoot`s are closed. This is why `TransferPair` exists.

I would probably need some help with improving this as I'm quite new to using Apache Arrow (and very new to using GitHub). But I have written a possibly improved implementation if this would be of interest and would be open to collaborating on rectifying this bug.

從 VectorSchemaRoot#addVector 開始，並閱讀 issue #301 中的相關討論。調查重新排列 FieldVectors 如何影響其底層緩衝區的所有權，以及 VectorSchemaRoots 在關閉時的行為。完成的標準是正確處理所有權轉移，且關閉 roots 不再導致所描述的緩衝區問題。

由索引模型根據 Issue 內容生成。