Extend CI and package metadata for Python 3.13/3.14 support

[Copilot]

This updates project automation and packaging metadata to cover Python 3.13 and 3.14. The goal is to ensure these versions are exercised in CI and explicitly declared as supported for distribution metadata.

• CI coverage expansion

  • Updated .github/workflows/testing.yml test matrix to run on Python 3.13 and 3.14 in addition to existing versions.

• Packaging metadata alignment

  • Added Python 3.14 classifier in both pyproject.toml and setup.py so published metadata matches CI-supported interpreter versions.

# .github/workflows/testing.yml
strategy:
  matrix:
    python-version: ["3.10", "3.11", "3.12", "3.13", "3.14"]

---

✨ Let Copilot coding agent set things up for you — coding agent works faster and does higher quality work when set up for your repo.

[Copilot]

Pull request overview

Expands OpenPIV’s declared and exercised Python version support by updating CI and distribution metadata to include Python 3.13/3.14.

Changes:

• Extend GitHub Actions test matrix to run on Python 3.13 and 3.14.
• Add Python 3.14 Trove classifier in both pyproject.toml and setup.py to align published metadata.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
.github/workflows/testing.yml	Expands CI Python version matrix to include 3.13/3.14.
pyproject.toml	Adds Python 3.14 classifier to Poetry package metadata.
setup.py	Adds Python 3.14 classifier to setuptools metadata.

Comments suppressed due to low confidence (1)

.github/workflows/testing.yml:14

• The CI workflow pins Poetry to 1.5.0, but the committed poetry.lock was generated by Poetry 2.3.2 (see poetry.lock:1). Poetry 1.5.0 may fail to read/install from this lock file, and adding 3.13/3.14 will make CI failures more likely. Please align the workflow to use a Poetry version compatible with the lock file (e.g., bump to 2.3.2+), or regenerate the lock with the pinned Poetry version and keep them in sync.

        python-version: ["3.10", "3.11", "3.12", "3.13", "3.14"]
        poetry-version: [1.5.0]

    steps:
    - uses: actions/checkout@v6