Suggestion: Glossary to the ic-ui-kit repo

## Summary
A lot of well seasoned projects has user guides, like this one from [NASA](https://nasa.github.io/openmct/static/files/Open_MCT_Users_Guide.pdf).

## 💬 Description
By adding a dictionary/user guide/glossary document, you make it easier for new contributors working on core logic to work on the project. It will also make the overall project documentation very good. To make it easier, you can host the user guide/glossary through GitHub pages.

## Why do we need it?
See above

The issue does not name any files, tests, or documentation entry points. Start by reviewing the repository's existing documentation and GitHub Pages setup, then define the glossary's scope and confirm that the completed guide is published and useful to new contributors.

Written by the indexing model from the issue text.