Update documentation for mindev, and add some handy debugging methods

[evankanderson]

Summary

While working on the PR rule types (upcoming), I started to write my own tool before being reminded of mindev. Our documentation had bit-rotted a little bit, but Jakub and Ozz helped straighten me out.

Change Type

Mark the type of change your PR introduces:

• Bug fix (resolves an issue without affecting existing features)
• Feature (adds new functionality without breaking changes)
• Breaking change (may impact existing functionalities or require documentation updates)
• Documentation (updates or additions to documentation)
• Refactoring or test improvements (no bug fixes or new functionality)

Testing

Manual test runs like the following:

TEST_AUTH_TOKEN="$(gh auth token)" go run ./cmd/dev ruletype test -e cmd/dev/examples/repository.yaml -p ../minder-rules-and-profiles/profiles/github/ghas.yaml -r ../minder-rules-and-profiles/rule-types/github/secret_push_protection.yaml

Review Checklist:

• Reviewed my own code for quality and clarity.
• Added comments to complex or tricky code sections.
• Updated any affected documentation.
• Included tests that validate the fix or feature.
• Checked that related changes are merged.

[coveralls]

coverage: 53.449% (-0.01%) from 53.46%
when pulling 336fedf on evankanderson:cleanup-mindev
into 275579a on stacklok:main.

[jhrozek]

thank you, the changes to properties.go are a nice usability improvement!