Add valve icons to library

[pogi7]

Goal:
Update figma design file to add valve icons to Stellar library

Things to explore:

• Spacing variables
• Base colors
• Themes
• Light and dark mode
• Aesthetic? (border radius, shadows, etc?)

Resources:

Example of Valve Icons:
https://kimray.com/sites/default/files/styles/video_thumbnail/public/uploads/training-demos/Column-Page-Block-Image.jpg?itok=aIFMemVg
(Figma files not available at the moment)