DOC: define typing aliases as Sphinx objects in aliases.rst

[dedlYTiTAN]

Summary
This PR converts the typing aliases in doc/source/reference/aliases.rst from a static list-table into proper Sphinx .. type:: directives.

What I changed

• Added .. module:: pandas.api.typing.aliases at the top of the file for correct scoping.
• Replaced the table entries with individual .. type:: blocks for each alias.
• Verified that descriptions still use the correct Sphinx roles for internal links (methods, classes, etc.).

I ran a local build to check the RST syntax. I encountered some local environment issues with pyarrow/timezones on Windows during the full User Guide build, but I've verified that the aliases.rst file itself parses correctly and the new directives are valid.

Fixes #63810

[mroeschke]

Closing this pull request as it does not follow our contribution guidelines. In particular:

• I suspect this pull request used AI in an irresponsible manner.
• This pull request does not meaningfully contribute to the project.
• This pull request addresses an issue already being worked on by another contributor

Additionally, 2 warning were already given about AI pull requests #63933 (comment) #63898 (comment) so we will be banning your contributions