[Bug]: indented 缩进树indent 无法使用函数传值

### Describe the bug / 问题描述

+ 插件版本 "@antv/g6": "4.8.24"
+ 官方文档[https://g6-v4.antv.vision/zh/examples/tree/indented/#filesystem]中支持函数传参

### Reproduction link / 复现链接

https://codesandbox.io/p/sandbox/interesting-sun-r65dl3?file=%2Findex.js%3A124%2C23

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

```js
indent: () => 230,
```
实际操作并不生效

### Version / 版本

4.x

### 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 linked CodeSandbox at index.js:124,23 and compare its indent callback with the official G6 v4 indented-tree example. Trace how the function-valued indent is handled in the indented tree layout, then verify that changing the callback value changes the rendered indentation.

Written by the indexing model from the issue text.