[UI Kit] v12 updates

[sarahill]

This will include token and api changes within polaris.

Gen 3 styles

Beta Give feedback

1. Publish to the Figma community
2. Publish internally
3. Deprecate or remove old styles
4. Create size variables
5. Create color variables
6. Update shadow tokens
7. Update type tokens
8. Update/add token references and maps
9. Update docs on each style page

Gen 3 components

Beta Give feedback

1. Publish to the Figma community
2. Publish internally
3. [UI Kit] Migrate components to space, size and border radius variables #10479
   43 of 43
   Figma UI Kit Tokens +2
   
4. Remove scratchpad sections and pages
5. [UI Kit] Migrate color styles to variables #10483
   53 of 53
   #gsd:36565 +1
   
6. Add space variables
7. Button updates
8. ButtonGroup updates
9. Banner updates
10. ProgressBar updates
11. Update components to use new Figma variables

Component api updates:

• [Button] Replace booleans with new props #10090
• Button deprecate props #10299
• ButtonGroup - Change segmented to variant, spacing to gap #9981
• Banner - status to tone #10050
• ProgressBar - color to tone #10049
• Layout.Section - replace booleans with new prop #9982