Python 3.14 migration

[mattwthompson]

Upstream dependencies:

• AmberTools
  • ParmEd (Rebuild for python 3.14 conda-forge/parmed-feedstock#46)
• OpenEye Toolkits
• DGL
• RDKit
• PyTorch (Rebuild for python 3.14 conda-forge/pytorch-cpu-feedstock#420 ?)
• OpenMM
• Psi4
• ForceBalance

[mattwthompson]

In practical terms, this is blocked by AmberTools and OpenEye until OpenFF 2.3.0 comes out¹. Without at least one of them, there's no way for mainline force fields to assign AM1-BCC partial charges, so there isn't really a point to packaging core infrastructure.

Footnotes

1. Currently it's in a release candidate: https://github.com/openforcefield/openff-forcefields/releases/tag/2025.10.0 ↩