Rebuild as a modern Selenium 4 automation framework

[yasirsavanur]

• replace the unfinished legacy helpers with a typed, packaged Selenium 4 + pytest framework
• add maintainable page objects, explicit waits, Chrome/Firefox/Grid driver creation, CLI configuration, and automatic failure evidence
• add data-driven smoke/regression/API/unit coverage and an 80% branch-coverage gate
• add GitHub Actions matrices for Python 3.10/3.12 and Chrome/Firefox
• rewrite the README as a portfolio-quality guide and add an MIT license

Validation

• ruff check .
• ruff format --check .
• pytest -m "unit or api" — 13 passed
• node --check demo_app/app.js
• python -m compileall -q src tests

The PR workflow runs the complete suite in real headless Chrome and Firefox and uploads HTML/JUnit reports plus any screenshots/page source captured on failure.