Add support for Python 3.13

[dfremont]

Description

Adds support for Python 3.13. Also unpins manifold3d as the API is now expected to be stable.

Note that using VerifAI will still fail on 3.13 until we update its dependencies too.

Issue Link

Checklist

• I have tested the changes locally via pytest and/or other means
• I have added or updated relevant documentation
• I have autoformatted the code with black and isort
• I have added test cases (if applicable)

Additional Notes

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 91.34%. Comparing base (394f205) to head (b76b724).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #328      +/-   ##
==========================================
+ Coverage   91.32%   91.34%   +0.02%     
==========================================
  Files          54       54              
  Lines       13577    13577              
==========================================
+ Hits        12399    12402       +3     
+ Misses       1178     1175       -3     

see 2 files with indirect coverage changes