Description

This PR adds a legend tab to PA EE.

• The legend tab displays general information related to the EE.

Relevant Technical Choices

Testing Instructions

• Open PSAT and navigate to PA EE.
• The page should open with the legend tab already selected and basic info about figures.

Additional Information:

Screenshot/Screencast

Checklist

• I have thoroughly tested this code to the best of my abilities.
• I have reviewed the code myself before requesting a review.
• This code is covered by unit tests to verify that it works as intended.
• The QA of this PR is done by a member of the QA team (to be checked by QA).

Fixes #857