🐛点击角头、维度的列头全部都是复制整个表格的数据，但没有高亮整个表格

### 🏷 S2 Version / S2 版本

| Package | Version |
| -------------- | ------- |
| @antv/s2 | 2.4.1 |
| @antv/s2-react | |
| @antv/s2-react-components | |

### 💻 Sheet Type / 表格类型

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

### 🖋 Describe the bug / 问题描述

点击角头、维度的列头全部都是复制整个表格的数据，但没有高量整个表格，实际复制行为UI表现不一致，且开启了
```javascript
{ copy: { enable: true, withHeader: true }
```
复制出来的数据没有角头

官网示例即可复现该问题

### ⌨️ Code Snapshots / 代码片段

```javascript
{ copy: { enable: true, withHeader: true }
```

### 🔗 Reproduction link / 复现链接

https://s2.antv.antgroup.com/examples/analysis/get-data/#get-multi-cell-data

### 📋 Steps to Reproduce the Bug or Issue / 重现步骤

点击角头、维度的列头全部都是复制整个表格的数据，但没有高量整个表格

### 😊 Expected Behavior / 期望行为

点击角头、维度的列头复制对应高亮单元格，或者高亮整个表格

### 😅 Current Behavior / 当前行为

_No response_

### 💻 OS / 操作系统

- [x] macOS
- [ ] Windows
- [ ] Linux
- [ ] Others / 其他

### 🌏 Browser / 浏览器

- [x] Chrome
- [ ] Edge
- [ ] Firefox
- [ ] Safari (Limited support / 有限支持)
- [ ] IE (Nonsupport / 不支持)
- [ ] Others / 其他

Start with the reproduction link and the PivotSheet configuration using copy.enable and copy.withHeader. Reproduce the behavior by selecting the corner or dimension column headers, then trace the selection and copy behavior in the TypeScript code. Done means the copied data matches the highlighted cells or table and includes the corner header when withHeader is enabled.

Written by the indexing model from the issue text.