A time-boxed spike, or proof-of-concept, for an EUI storybook.

Needs

• Install Storybook inside the EUI repo
• Generate the needed Storybook configuration files and scripts
• At least one example story (if fundamentally different than the examples that Storybook auto-generates)
• Ensure that Storybook serves locally without issue
• The work should be contained to a feature branch (or similarly gated) to not interfere with production work

Key discovery points

These may not be fully answerable when this issue is closed, but I want to put them on our radar as we start working on this stuff.

• Feasibility of wholesale replacing src/docs with Storybook
• Feasibility of publishing Storybook with Chromatic