Update to Python 3.14 and deprecate Python 3.9

[danineamati]

Describe the proposed feature

1. Remove Python 3.9 from the available versions
2. Add Python 3.14
3. Upgrade to poetry 2+
4. Update pyproject.toml to match Python 3.10 to 3.14
5. Update poetry lock

Motivate the proposed feature
Python 3.9 is no longer supported by many libraries and is at end-of-life: https://devguide.python.org/versions/.