Type hints for `pathlib.types`

Feature or enhancement

The pathlib.types module is new in 3.14, and contains a single public class: pathlib.types.PathInfo.

This module also contains a few private classes: _PathParser, _JoinablePath, _ReadablePath and _WritablePath.

As the pathlib.types module is not imported by pathlib, I think we're free to add proper type annotations to the entire module, including the private classes. I think this will help clarify the interface.

I'd like these hints to be compatible with the oldest version of Python still receiving security updates (3.9 at time of writing) because I'm hoping to provide a PyPI package from this module.

Linked PRs

• gh-131639

首先检查 pathlib.types 模块和关联的 PR gh-131639，以确定工作的当前状态。检查如何使注解保持与 Python 3.9 的兼容性，并考虑 issue 中提到的公共类和私有类。当该模块具备完整且兼容的类型提示，同时不改变其预期接口时，即可视为完成。