Add CUDA 13x extension

[garrettwrong]

Adds CUDA 13 support. Use latest cufinufft==2.5.0 for new gpu_13x packaging, leave prior 2.4.0 for 12x to maintain that environment the way it was.

Also supports migration of CI environments towards CUDA 13.1.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.84%. Comparing base (9caa2a8) to head (77c4c0e).
⚠️ Report is 4 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #1369   +/-   ##
========================================
  Coverage    90.84%   90.84%           
========================================
  Files          135      135           
  Lines        14658    14658           
========================================
  Hits         13316    13316           
  Misses        1342     1342           

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[garrettwrong]

Merging. Will begin setting up the new (Python 3.10, CUDA 13) CI envs.