Flesh out README's contributing section

Summary

right now the readme has only a hyperlink to the open issues. I'd like to see something more informative that also provides a snapshot of the project's outlook / progress

Proposed Solution

I'm not sure if there's a way to use badges to dynamically show milestones and their progress? or perhaps listing open issues by type?

Alternative

perhaps there's a gh-actions thing we can make to update the README to reflect issues and milestones dynamically

Additional Context

I know there are variations of progress bars that github's markdown supports. that might be of use.

Code of Conduct

[X] I agree to follow this project's Code of Conduct

Todo

[ ] README has a more informative overview of milestones
[ ] hyperlinks or infographics have dynamic links to appropriate content
[ ] progress (progress bars or whatever) is made in the README w/o editing the README

Graqr / Threshr