Document why DirExt::access on Windows doesn't use their faccess equivalent

I noticed that your Windows implementation of `DirExt::access` just tries opening the file.

I understand if [_access, _waccess, t_access](https://learn.microsoft.com/en-us/cpp/c-runtime-library/reference/access-waccess?view=msvc-170) or [_access_s, _waccess_s, _taccess_s](https://learn.microsoft.com/en-us/cpp/c-runtime-library/reference/access-s-waccess-s?view=msvc-170) from the Microsoft C Runtime impose additional dependencies you want to avoid, and that the Win32 API-native version's [overcomplicated credentials](https://blog.aaronballman.com/2011/08/how-to-check-access-rights/) blow up to six pages in the [faccess](https://github.com/Freaky/faccess/) crate's Windows implementation ([Link to the source file](https://github.com/Freaky/faccess/blob/master/src/lib.rs), MIT-licensed) once you address various edge cases.

However, I was unable to find any clear documentation for the rationale behind that. (Which I'm guessing is "auditing burden".)

Could that be improved, please?

Comienza localizando la implementación para Windows de DirExt::access y lee cómo comprueba actualmente el acceso abriendo el archivo. Compara ese enfoque con las Microsoft CRT APIs enlazadas y la implementación para Windows de faccess; después, documenta la justificación del proyecto, incluidas las preocupaciones sobre dependencias o auditoría que estén confirmadas. Se considera terminado cuando la justificación sea clara para los lectores sin cambiar la implementación.

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