Fill out user documentation (nice-to-have)

[gilesknap]

Summary

The docs now have a CLI reference (with the shared/backend command slices) and an environment variables reference. The Diátaxis tutorial / how-to / explanation sections are still thin.

This is a nice-to-have. A lot of this material overlaps with the wider framework docs at https://epics-containers.github.io/, so in many cases the better move is to link out to that site rather than duplicate content here. We should only write edge-containers-cli-specific pages where this tool genuinely differs.

Candidate content

• Tutorial: first steps with the DEMO backend — a zero-setup quick win (ec -b DEMO ps / monitor), so new users have something actionable immediately after installation without a cluster.
• How-to: configure your environment — set EC_SERVICES_REPO / EC_TARGET / EC_CLI_BACKEND once, plus shell tab-completion (ec --install-completion), which the CLI supports but isn't documented.
• How-to: deploy and manage a service end-to-end — the deploy → ps → logs → stop/start → delete loop.
• Explanation: backends & the "thin wrapper" philosophy — GitOps (ArgoCD) vs direct K8s, and how --verbose/--dryrun reveal the underlying git/kubectl/helm/argocd commands.
• Reference: glossary — service, IOC, target, repo, instance, version.

Note

Before writing any of the above, check whether https://epics-containers.github.io/ already covers it and link there instead.