Define icon design standards

[luxaritas]

Some example icon design guidelines from various systems:

• https://fontawesome.com/docs/web/add-icons/upload-icons/icon-design
• https://material.io/design/iconography/product-icons.html#design-principles
• https://www.ibm.com/design/language/iconography/ui-icons/design/
• https://design.gitlab.com/product-foundations/iconography/

[luxaritas]

Some things that would be good to include, given what other design systems do (in addition to anything else we think is important to our system):

• Grid use
• Keylines
• Balance
• Padding
• Stroke
• Corners/Border radius
• Angles
• Color
• Perspective
• Lighting/shadow/etc
• Icon meaning