🙏期望交叉表可以同时配置多个小计、总计

### 🖋 Description

期望交叉表可以同时配置多个小计、总计
### 🏞 What problem does this feature solve

目前交叉表只能配置一个小计、总计，无法配置同时展示“总计（加和）”、“总计（平均）”、“小计（加和）”、“小计（平均）”，希望S2可以提供配置多个小计、总计的能力。
### 🧐 Suggest the API

| name | type | default | description |
| ---- | ---- | ------- | ----------- |
| - | - | - | - |

No files, tests, or entry points are named. Start by reviewing S2's existing cross-table subtotal and total configuration and its API, then determine how multiple aggregations should be represented. Done should allow simultaneous sum and average subtotals and totals.

Written by the indexing model from the issue text.