v4.5.4

• Add Python 3.14 support.
• Drop Python 3.9 support (end-of-life since October 2025); python_requires is now >=3.10.
• Refine the Python compatibility CI workflow: reduce the test matrix to ubuntu-latest with Python 3.10 (floor) and 3.14 (ceiling), and bump actions/checkout and actions/setup-python to current major versions.