feat: Automate CSS Color Variable Generation from Figma JSON

[brianacnguyen]

Description

• This PR seeks to add automation scripts to convert json files to css files for brand colors and themed colors

Related issues

Fixes: #662

Manual testing steps

1. run node scripts/brandColors.jsonToCss.js or node scripts/themedColors.jsonToCss.js

Screenshots/Recordings

Before

After

Pre-merge author checklist

• I’ve followed MetaMask Coding Standards.
• I've clearly explained what problem this PR is solving and how it is solved.
• I've linked related issues
• I've included manual testing steps
• I've included screenshots/recordings if applicable
• I’ve included tests if applicable
• I’ve documented my code using JSDoc format if applicable
• I’ve applied the right labels on the PR (see labeling guidelines). Not required for external contributors.
• I’ve properly set the pull request status:
  • In case it's not yet "ready for review", I've set it to "draft".
  • In case it's "ready for review", I've changed it from "draft" to "non-draft".

Pre-merge reviewer checklist

• I've manually tested the PR (e.g. pull and build branch, run the app, test code being changed).
• I confirm that this PR addresses all acceptance criteria described in the ticket it closes and includes the necessary testing evidence such as recordings and or screenshots.

[metamaskbot]

Builds ready [5bc04dc]

Storybook: Storybook

[metamaskbot]

Builds ready [f9bcd98]

Storybook: Storybook

[metamaskbot]

Builds ready [6881475]

Storybook: Storybook