Switch from docopt to typer

[jsf9k]

🗣 Description

This pull request switches from docopt to typer for our CLI argument-parsing needs.

💭 Motivation and context

I noticed that installing docopt generates warnings because it still uses a setup.py file versus a pyproject.toml file. Investigating further, I found that docopt hasn't seen any updates since 2014. I figured now would be a good time to start looking at alternatives.

The main two alternatives right now are click and typer. The former is a bit more verbose, whereas the latter is a bit more opinionated but also more Pythonic. typer uses click under the hood and leverages type hints to do some work for you. Both automatically generate tab completion for various shells.

See #176 for the click implementation. We can choose which one we like better.

🧪 Testing

All automated tests pass.

✅ Pre-approval checklist

• This PR has an informative and human-readable title.
• Changes are limited to a single goal - eschew scope creep!
• All relevant type-of-change labels have been added.
• I have read the CONTRIBUTING document.
• These code changes follow cisagov code standards.
• Tests have been added and/or modified to cover the changes in this PR.
• All new and existing tests pass.
• Bump major, minor, patch, pre-release, and/or build versions as appropriate via the bump_version script if this repository is versioned and the changes in this PR warrant a version bump.
• Create a pre-release (necessary if and only if the pre-release version was bumped).

✅ Pre-merge checklist

• Finalize version.

✅ Post-merge checklist

• Create a release (necessary if and only if the version was bumped).

[jsf9k]

I personally like the click implementation better.

[dav3r]

I think both typer and click seem fine for our needs. I asked Google about it and here's what it came back with:

Pick Typer if: You want a modern developer experience with excellent autocompletion and less boilerplate. It is ideal if you are already using FastAPI, as it shares the same design philosophy.

Pick Click if: You need a proven, stable tool with maximum control and minimal dependencies. It is often preferred for very large, complex CLI structures where explicit control over every parameter is necessary.

Hybrid Approach: Because Typer is built on Click, you can use Typer for your main interface but drop down into Click for advanced features that Typer might not yet support.

That being said, I have no major preference here and will gladly go with whichever one our team feels more strongly about.

Additional info from Google:

[felddy]

Thank you for writing up both of these implementations. The side-by-side is useful.

That said, I prefer the click implementation over this one. I appreciate the more explicit syntax.

• #176

[jsf9k]

We have decided to go with #176.