Update CI and add python 3.14 support

[mworion]

@brandon-rhodes:
This pull request follows path 1) of our discussion. I added the python 3.14 support and updated the actions to the latest versions.
The action is now shorter and the accelerated version are now tested against all python versions (was: only latest).
I added some comments with hints, what to be done when adding python 3.15 support.
Unfortunately some of the runners (ubuntu-arm and macos-intel) do not have a tag '-lastest', so also in future there should be a look to it.
Michel

[mworion]

@brandon-rhodes:
I checked if your last quick integration was able to offer python3.14 support on pypi. This was not the case. As result sgp4 does not support 3.14 officially. if you have some time, please check to move the PR forward as I also would be happy to offer 3.14 on my App which has a dependency to skyfield and sgp4 as result.
Best
Michel

[neutrinoceros]

note that I opened #151, with a slightly (yet not fully) overlapping scope; this other PR could also add explicit support for Python 3.14, but would also supposedly support Python 3.15+¹

Footnotes

1. unless abi3's forward compatibility is ended in this cycle, which seems unlikely but not entirely impossible with PEP 803 and 809 being actively discussed right now ↩

[brandon-rhodes]

@mworion — I looked at this and thought, didn't I just do this? How could I not have missed this PR while adding all that 3.14 logic? And it turns out, it was PyEphem that now is compiled for 3.14. Not sgp4. 😳

@neutrinoceros — I have now merged this PR! Can you rebase yours atop this one without undue trouble?

[neutrinoceros]

done !

[mworion]

@brandon-rhodes: Many thanks for merging :-)