`path.join` should not be used with `file:\\` URL

`path.join` should not be used with `file:\\` URL,  it's unreliable.

```js
// Node.js v18
const path = require('path');
path.join('file:\\', process.cwd());
// 'file:\\C:\\Users\\xxx\\nodejs\\v18.xx'

// Node.js v24
const path = require('path');
path.join('file:\\', process.cwd());
// '.\\file:\\C:\\Users\\xxx\\nodejs\\v24.xx'
    ^
```
