Support Python 3.14

[crnh]

Add support for Python 3.14. This requires Pydantic to support Python 3.14 as well.

[crnh]

Pydantic now supports Python 3.14, but Python.NET doesn't support it yet.

[JoachimBT]

Python.NET doesn't support it yet

ref: pythonnet/pythonnet#2610

[arsymbol]

Now Python.NET 3.1.0 supports Python 3.14
ref: https://github.com/pythonnet/pythonnet/releases/tag/v3.1.0

[crnh]

@arsymbol thanks for the heads up! We'll add support for Python 3.14 soon!