docs: expand Socket CLI comparison with structured section

[isteelfelix]

Improves the Socket CLI section in the comparison table with clearer explanation of its strengths and limitations.

[Copilot]

Pull request overview

This PR expands the README’s “How it compares” section by adding a short, structured “About Socket CLI” subsection to clarify Socket CLI’s strengths/limitations alongside CVE Lite CLI’s positioning.

Changes:

• Add an “About Socket CLI” subsection under “How it compares”.
• Provide a brief narrative comparison emphasizing supply-chain analysis vs. offline/account-free usage.

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[sonukapoor]

Welcome to the project, @isteelfelix! 🎉

One thing before we can merge: PR #369 was just merged and updated README.md significantly (hero section, OWASP positioning, unique combination claim). Your branch is now behind main and will need a rebase to apply cleanly.

Could you run:

git fetch origin
git rebase origin/main
git push --force-with-lease

Once that's done, we'll get this merged. If you're interested in contributing more, feel free to browse the open issues - there's plenty of interesting work across docs, features, and case studies. Would love to have you involved.