Add CI/CD workflows and update docs config

[google-labs-jules]

This PR adds GitHub Actions workflows for Continuous Integration (CI) and Continuous Deployment (CD).

CI:

• Runs tests on Python 3.10 and 3.11 for every push and pull request to main.
• Installs dependencies from pyproject.toml and runs tests using unittest.

CD:

• Deploys the MkDocs documentation to GitHub Pages on every push to main.
• Uses mkdocs-material theme (added to dependencies and config).

Also includes cleanup of site/ directory from .gitignore.

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PR created automatically by Jules for task 13537202722892185221 started by @stevevanhooser

[google-labs-jules]

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