Add Chennai FOSS demo-command guide under feature announcements

[Copilot]

This adds a Chennai FOSS-specific guide that reduces the project’s broad CLI surface into a single Go-based demo flow from process alignment through CI/CD, GitOps, and monitoring. The content is now located under feature-announcements/chennai-foss-2026 so it sits with the event-specific material instead of a separate top-level docs folder.

• What changed

  • Added feature-announcements/chennai-foss-2026/demo-command-list.md
  • Moved the Chennai FOSS markdown content out of the temporary top-level chennai-foss/ location
  • Kept the content focused on a minimal, high-signal live demo sequence

• Content added

  • Recommended command flow for a Go service:
    • process-first
    • scaffold devcontainer
    • scaffold unittest
    • scaffold gha
    • scaffold argocd
    • scaffold sre
  • Talk-track guidance tying each command to:
    • platform engineering
    • templatisation / golden paths
    • IDP-style self-service

• Why this layout

  • Co-locates Chennai FOSS material with the existing feature-announcements/chennai-foss-2026 assets
  • Makes the demo guide discoverable alongside the presentation entrypoint

python -m cli.devopsos process-first --section mapping
python -m cli.devopsos scaffold devcontainer --languages go --cicd-tools docker,terraform --kubernetes-tools kubectl,helm,k9s,argocd_cli,flux
python -m cli.devopsos scaffold gha --name go-demo --languages go --type complete --kubernetes --k8s-method argocd
python -m cli.devopsos scaffold argocd --name go-demo --repo https://github.com/your-org/go-demo.git --path k8s --auto-sync
python -m cli.devopsos scaffold sre --name go-demo --team platform --slo-target 99.9