Add contributing guide and Taskfile

[blackary]

• Added CONTRIBUTING.md
• Separated out linting and testing in github actions
• Some general code cleanup with new ruff rules
• Added Taskfile to simplify steps for linting, testing and generating new tests locally

[randyzwitch]

@blackary, I merged #217 thinking this PR encapsulated that one's changes. However, now this doesn't pass.

I see in our test requirements, we don't include streamlit 1.34...is that for the #222 reasons or something else? Given that streamlit is 1.38, I wonder if we need to be even more restrictive?