表格自定义单元格icon能否支持多个icon🙏

### 🏷 Version

| Package | Version |
| -------------- | ------- |
| @antv/s2 | 1.51.1 |
| @antv/s2-react | |
| @antv/s2-vue | |

### Sheet Type

- [x] PivotSheet
- [x] TableSheet
- [ ] GridAnalysisSheet
- [ ] StrategySheet
- [ ] EditableSheet

### 🖋 Description

表格单元格自定义icon能否支持多个icon，目前好像一个单元格只能显示一个icon？

我们的需求：使用tooltip给单元格添加备注信息
我们期望能提供单元格右上角添加tag，如下：

--忽略蓝色箭头

查阅文档后发现自定义单元格icon有许多存在限制的点：只提供数值左右的icon，icon数量只能一个

目前希望自定义单元格icon可以支持多个icon，有余力的话也希望可以支持图中类似单元格角标的功能

### 🏞 What problem does this feature solve

### 🧐 Suggest the API

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

No source file, test, or implementation entry point is named. Start by locating the existing custom-cell-icon documentation and API, then trace how icons are rendered for PivotSheet and TableSheet. Done should be defined as a reviewed API and tests or examples covering multiple icons, with corner badges treated as a separate optional scope.

Written by the indexing model from the issue text.