Enhance GitHub Pages repository README

[musaabhasan]

Summary

• Replace the one-line repository README with a clearer GitHub Pages project overview.
• Align the repository with Musaab Hasan's public profile themes: security governance, business continuity, EdTech, applied research, IoT security, and software delivery.
• Add links to the public website, professional profile, publications, Google Scholar, LinkedIn, and featured repositories.
• Note the separate musaabhasan/musaabhasan profile README repository needed for the GitHub profile page itself.

Verification

• Markdown content reviewed locally for formatting and link coverage.