feat(breadcrumb): draft of breadcrumb web component

[mndonx]

Summary

This PR adds a Breadcrumb menu web component to the UI Kit.

How to review this pull request

• Run npm run develop
• Open the Emulsify instance
• Click on the Breadcrumbs link in the sidebar
• Ensure that the breadcrumb works as expected.

[joetower]

@mndonx This looks good to me, nice work!

My only question is: should we add a current or active state? Maybe a status option or something which we could style to distinguish it as the current path item - which would not be a linked item? In this case, item level 3 would get the current/active state.

[mndonx]

@joetower Thanks Joe! I've added contingency for the "current" item so it is not a link and has a special class. That is ready for review.

However, I still have a couple issues to resolve.

• @cienvaras showed us how to include some common variables in a different file, but I totally forgot to write it down or record it, so I will need a refresher on how it is done since that was a few weeks ago now! I'd like to include that here.
• The colors are not passing contrast tests, but I don't want to mess with the variables. What is the process for changing the tokens?

[mndonx]

@joetower @cienvaras I've updated this PR to have a way to use a reusable class (visually-hidden.) Let me know what you think of the solution (I read about it in the Lit documentation.)

There is definitely still an issue of color contrast. I added an issue in the Emulsify UI Kit to address the contrast issues across the project. I wonder if I should wait on that, or move this forward?