Add support for python 3.14 Free-threaded

[jerry102039]

PEP 779 : from various experiments it’s very clear free-threaded Python has tremendous potential benefit. It’s not a simple drop-in solution – some code will have to be redesigned to make the most of the new capability, as well as avoid performance pitfalls – but it can achieve higher performance, significantly lower latency and new thread-based functionality when embraced.

[vxlk]

Eagerly awaiting this