Abstract color palettes out into a reusable Vue component

Creates the FoundationsColorPalette and ColorContrastScore components to render color palettes in the Foundations > Color page.

This also migrates the Blue color palette to those new components as a first iteration. Other palettes will be migrated in follow-ups.

There should be no visual change as this only reproduces the existing behavior with a reusable component:

Before	After

Closes #1384 (closed)