[WIP] Add command reference

[craddm]

✅ Checklist

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🚦 Depends on

⤴️ Summary

Adds a new top-level section to the documentation. This section shows the documentation for all of the available dsh commands using Typer rich console formatting.

🌂 Related issues

🔬 Tests

Documentation only

[github-actions]

Coverage report

This PR does not seem to contain any modification to coverable code.