Add support for Python 3.14

[MicahGale]

Description

Python 3.14 is out, and I do love adding support for a new version of Python ASAP (#3164). As I learned last year though our dependencies do not do so as quickly.

Tasks

• [ ] Update CI workflows to test against Python 3.14
• [ ] Update CI workflows to build for python 3.14 (Conda-forge)
• [ ] Ensure python dependencies support python 3.14
  • [x] Numpy
  • [ ] VTK: this is biggest hand up usually. They have built the infrastructure , but have yet to ship
  • [x] h5py
  • [x] scipy
  • [x] ipython
  • [x] matplotlib
  • [x] pandas
  • [x] lxml
  • [x] uncertainties
  • [x] setuptools
  • [x] endf
• [ ] Deciding on how to handle stable free-threading now available in 3.14 (#3640)

Alternatives

Compatibility

[MicahGale]

I'm impressed @paulromano: you added Python 3.14 support for ENDF back in August.