Add cross-platform local serving commands

[chambear2809]

Summary

• add macOS, Debian/Ubuntu Linux, and Windows PowerShell commands for the HTTPS lab setup
• add platform-specific commands for the insecure HTTP smoke test
• use the public npm registry explicitly so http-server is not routed through a restricted private registry

Validation

• Hugo production build passed
• git diff --check passed
• local http-server startup tested successfully with the documented public registry override

[chambear2809]

Closing while the Bonus Bonus Activity work is still in progress; changes remain on the branch for follow-up.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-06T03:24:37.528165Z	7676112	PR opened

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