Update minimum Python version to 3.10 (remove EOL 3.9)

[Copilot]

Python 3.9 reached end-of-life. Update minimum supported version to 3.10 and ensure test matrix covers all GA releases (3.10-3.13).

Changes

• setup.py: Remove 3.9 classifier, set python_requires=">=3.10"
• .github/workflows/test.yml: Test matrix now ["3.10", "3.11", "3.12", "3.13"]
• .github/workflows/publish.yml: Build uses Python 3.10

Note: Python 3.14 support will be added in a separate issue once compatibility issues are resolved.

Original prompt

Python 3.9 is EOL. Replace all uses of "minimum version with 3.10". Also ensure that the test matrix and pypi metadata includes only all GA python releases (3.10 up to 3.14 iiuc).

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This change is 

[dhalperi]

@copilot > Python 3.14 was released on 7 October 2025. For full details, see the changelog.

https://docs.python.org/3/whatsnew/3.14.html

[Copilot]

@copilot > Python 3.14 was released on 7 October 2025. For full details, see the changelog.

https://docs.python.org/3/whatsnew/3.14.html

Added Python 3.14 to the supported versions in commit cdcac10. The test matrix and PyPI classifiers now include 3.10, 3.11, 3.12, 3.13, and 3.14.

[dhalperi]

@copilot So tests don't pass for 3.14. Can we revert back to 3.10-3.13 and also create an issue for adding 3.14 support?

[Copilot]

@copilot So tests don't pass for 3.14. Can we revert back to 3.10-3.13 and also create an issue for adding 3.14 support?

Reverted Python 3.14 support in commit 3db1d45. The test matrix and PyPI classifiers now only include 3.10-3.13.

I don't have permissions to create issues, but here's the suggested issue content for adding Python 3.14 support:

Title: Add Python 3.14 Support

Description:
Python 3.14 was released on October 7, 2025. Add support once compatibility issues are resolved.

Tasks:

• Investigate test failures on Python 3.14
• Fix any compatibility issues
• Add Python 3.14 to setup.py classifiers and test matrix
• Verify all tests pass

Reference: Tests currently fail on Python 3.14 (reverted in 3db1d45)

[dhalperi]

@dhalperi reviewed 3 of 3 files at r1, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @copilot)