Add GitHub workflows and strengthen static tests

[G-Fourteen]

Summary

• add a pull request workflow that exercises pytest on every PR update and reports the results
• create a main branch pipeline that builds static artifacts, runs tests, echoes deployment status, and emits test summaries
• extend the JavaScript and CSS checks to cover every declared function and the flattened single-tone styling, and surface new workflow badges in the README

Testing

• pytest

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https://chatgpt.com/codex/tasks/task_b_6906305275bc83299da2febeae7c0295