Big topic - "t-shirt" (border/radius/spacing/content) naming and granularity

[taysea]

These tokens are the "t-shirt" sized border/radius/spacing/content.

• [ ] For our semantic dimension scale, should we use a numeric system or t-shirt sizes?
• [ ] How many steps are needed to achieve our desired level of granularity?
• [ ] What is "subjective" desire for granularity vs any more "objective" reasoning to adding steps to the t-shirt scale (e.g., previously we've discussed value of have 2:1 ratio steps like 16px, 8px or 32px, 16px)?

Subtasks:

• https://github.com/grommet/hpe-design-system/issues/3905
• https://github.com/grommet/hpe-design-system/issues/3912