Support Python 3.14 (bump requires_python upper bound)

[joshwilhelmi]

Summary

kokoro-onnx currently specifies requires_python: <3.14,>=3.10 in its metadata, which prevents installation on Python 3.14.

Context

• onnxruntime 1.24.4 already ships cp314 wheels (macOS arm64, Linux x86_64/aarch64, Windows amd64/arm64) and lists Programming Language :: Python :: 3.14 in its classifiers
• kokoro-onnx is a pure Python package (py3-none-any wheel) — no compiled extensions that could break
• Python 3.14 has been stable since October 2025
• The other runtime deps (numpy, espeakng-loader, phonemizer-fork) all support 3.14

Request

Bump requires_python from <3.14,>=3.10 to <3.15,>=3.10 (or drop the upper bound entirely).

Happy to open a PR if preferred.

[RavSinghChandan]

Hit this too when trying to install on 3.14. It's just the requires-python = ">=3.10,<3.14" cap in pyproject.toml blocking it — and like you said, onnxruntime already ships 3.14 wheels, so nothing actually breaks.

Should be a quick one — bump the cap to allow 3.14. Happy to open a PR for it, want me to?