[Bug]: 脑图树-子节点自动两侧分布 通过回调函数修改defaultEdge线的样式不生效

### Describe the bug / 问题描述

defaultEdge: {
type: 'cubic-horizontal', // 水平贝塞尔曲线
style: (cfg) => {
console.error('sadsdasdasdasd', cfg);
return {
stroke: '#497bff', // 设置边的颜色
lineWidth: 2, // 设置线宽（可选）
endArrow: true // 设置是否显示箭头（可选）
}
}
},

### Reproduction link / 复现链接

_No response_

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

_No response_

### Version / 版本

4.x

### OS / 操作系统

- [ ] macOS
- [x] 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

No reproduction link, source file, or test is provided. Start by reproducing the reported defaultEdge callback behavior in G6 4.x on Windows and Chrome with the configuration shown; done means the callback's stroke, lineWidth, and endArrow settings visibly affect the tree edges.

Written by the indexing model from the issue text.