feat(packaging): migrate packages out of setup.py

[onerandomusername]

Summary

Previously, new modules or files would need to be explicitly added to setup.py

This moves the configuration to pyproject.toml and drops the requirement they must be explicit. At this point, this means the only reason for setup.py is our custom version indicators.

Checklist

• If code changes were made, then they have been tested
  • I have updated the documentation to reflect the changes
  • I have formatted the code properly by running pdm lint
  • I have type-checked the code by running pdm pyright
• This PR fixes an issue
• This PR adds something new (e.g. new method or parameters)
• This PR is a breaking change (e.g. methods or parameters removed/renamed)
• This PR is not a code change (e.g. documentation, README, ...)

[shiftinv]

Wouldn't this change become obsolete with #1323?

[onerandomusername]

it would be obseleted by 1323, but that pull seems like it will take longer to be passed, and I want to move as much as possible out of setup.py.

[onerandomusername]

I've also tested locally and this still works with our minimum defined setuptools version of 61.

[shiftinv]

root@3fc6fd26ac00:/disnake# wheeldiff dist_master/disnake-2.11.0a0-py3-none-any.whl dist/disnake-2.11.0a0-py3-none-any.whl 
root@3fc6fd26ac00:/disnake# echo $?
0

sure, why not. seems fine to me.