[WIP] Add support for Python 3.14

[Copilot]

• Explore repository structure and understand Python version configuration
• Update pyproject.toml to add Python 3.14 classifier
• Update pyproject.toml to change requires-python constraint to include 3.14
• Update CI workflow to test against Python 3.14
• Update uv.lock to reflect new Python version constraint
• Run tests to verify changes work correctly
• All tests passing (361 passed, 6 xfailed)
• Type checking passing with mypy
• Code formatting verified with ruff

Summary of changes:

• Added Programming Language :: Python :: 3.14 classifier in pyproject.toml
• Updated requires-python from >=3.9,<3.14 to >=3.9,<3.15
• Added Python 3.14 to CI test matrix
• Updated uv.lock with new Python version constraint

Original prompt

Add suport for python 3.14

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