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

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After

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