* feat: add GitHub Actions CI workflow
Add CI workflow that runs on pushes and pull requests to main branch.
Tests against Python 3.11, 3.12, and 3.13 using the existing check.sh script.
The workflow:
- Sets up Python environment
- Installs Poetry and dependencies
- Uses caching for faster builds
- Runs check.sh which includes: ruff format, ruff check, mypy, pytest, and poetry check
* fix: run check.sh with poetry to access dev dependencies
The check.sh script needs to run within the Poetry virtual environment
to have access to dev dependencies like ruff, mypy, and pytest.
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Co-authored-by: Claude <noreply@anthropic.com>
