Demonstrate lifecycle safety and automation contracts

[codeforester]

Summary

Add a realistic scenario that demonstrates the operational guarantees users need from a production CLI.

Scope

• Include a safe dry-run workflow for a state-changing command.
• Demonstrate human output alongside JSON output and structured errors.
• Exercise debug logging, log-file selection, sensitive-argument redaction, temporary paths, and cleanup.
• Show exit-code behavior for success, validation failure, and operational failure.

Acceptance criteria

• Tests assert stdout, stderr, exit status, redacted logs, and JSON records.
• The dry-run path performs no state mutation.
• The scenario is deterministic and works without network access or credentials.

Non-goals

Do not add real cloud operations or claim that redaction replaces secret management.