Root Dockerfile for CLI (local/dev)

[ulises-jeremias]

Summary

Dockerfile usable before publish-docker hardens multi-arch.

CNA mapping

CNA: root Dockerfile.

Acceptance criteria

• Image runs CLI --help
• Documented in README

Blocked by

none

Blocks

none

Reference

Parity matrix (workspace): knowledge/create-python-app-parity-matrix.md
Reference repo: https://github.com/Create-Node-App/create-node-app

Parent epic

#10