当gpt返回的消息内容很长时，ChatScrollObserverHandleMode.generative 不能保持手势主动滚动的位置

[codon19]

Version

1.26.2

Platforms

Android, iOS

Device Model

iPhone 12(iOS 18.5)

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How to reproduce?

在使用ChatScrollObserverHandleMode.generative时，列表反转渲染reverse: true, 当回复的流式内容很长时，从上往下滚动不会保持手势主动滚动的位置，cacheExtent设置很大才行，请问这个可以解决？

chatObserver.standby(
    mode: ChatScrollObserverHandleMode.generative,
    refItemIndex: 0,
    refItemIndexAfterUpdate: 0,
  );

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Example code (optional)

Contact

No response

[LinXunFeng]

使用 ListView 且消息太长是无法避免这个问题的，可查看该回复 #111 (comment)

我理解上要解决这个问题，需要结合 CustomScrollView 的 center 去处理，插入的新自增消息位于 center 下的 sliverList，待消息接收完成后整合回 center 上的 sliverList。