🙏树状结构折叠的方式能不能多一种展示样式

### 🖋 Description
两个需求
1.如图，大类、中类、小类其实就是角头，树状结构用行表示，现在S2里用列表示，用列表示树状结构一多，这一列就很宽，希望可以采用如图的方式，第一张图是展开的样式，第二张图是收缩的样式；
2.分组合计和总合计，希望可以多行，比如一行合计是求和，另一行合计是求平均值。

### 🏞 What problem does this feature solve

### 🧐 Suggest the API

No files, tests, or API entry points are identified. Start by tracing S2's tree-structure rendering and grouped and grand-total aggregation paths, then clarify the desired expanded and collapsed layouts and multi-row sum and average totals. Done means both display styles and multiple aggregate rows are supported and demonstrated.

Written by the indexing model from the issue text.