new conda python Windows layout

[loriab]

This fixes the parameters import for the conda-forge py315 module for Windows after the new layout https://conda-forge.org/blog/2026/09/03/python-315/#a-more-unixy-layout-on-windows . I've patched the dftd3-python conda package and tested it against psi4, so there's no hurry.

If there's confidence the 3 * ".." path is only used by conda-forge, I can make this change shorter.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 63.50%. Comparing base (5bf48d7) to head (92fd45a).

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #240      +/-   ##
==========================================
+ Coverage   63.49%   63.50%   +0.01%     
==========================================
  Files          47       47              
  Lines        6821     6823       +2     
  Branches     2422     2422              
==========================================
+ Hits         4331     4333       +2     
  Misses       1182     1182              
  Partials     1308     1308              

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[awvwgk]

Fine with this change, note that we do distribute an sdist (via GH release and PyPI release) which ships the parameters.toml in the Python package and does not need this change.

[loriab]

Fine with this change, note that we do distribute an sdist (via GH release and PyPI release) which ships the parameters.toml in the Python package and does not need this change.

Good to know, thanks. Looks like dftd3-python-feedstock and simple-dftd3-feedstock keep aligned on the GH src.