Adds Size token [LG-3607]

.changeset/afraid-snails-trade.md

@@ -0,0 +1,5 @@
+---
+'@leafygreen-ui/tokens': minor
+---
+
+Adds `Size` token

packages/tokens/src/index.ts

@@ -4,6 +4,7 @@ export { default as fontFamilies } from './fontFamilies';
 export { default as fontWeights } from './fontWeights';
 export { default as hoverRing } from './hoverRing';
 export { Mode } from './mode';
+export { Size } from './size';
 export { default as spacing } from './spacing';
 export { default as transitionDuration } from './transitions';
 export { BaseFontSize, default as typeScales } from './typeScales';

packages/tokens/src/size.ts

@@ -0,0 +1,8 @@
+export const Size = {
+  XSmall: 'xsmall',
+  Small: 'small',
+  Default: 'default',
+  Large: 'large',
+} as const;
+
+export type Size = (typeof Size)[keyof typeof Size];