feat(layers): Update info to match figma specs

relates to: #1200 (closed)

From: #1200 (closed) we updated the shadow styles in figma. This MR brings those styles into our documentation.

In this MR:

• Update styles for sm, md, and lg shadows to match figma styles.
• Update component references for each shadow type
• Update illustrations for all; sm, md, lg, interactive, and scrolling examples to follow new example styling
• Remove reference to base in sm, md, lg.
• Update definition for large shadow
• Delete deprecated shadow illustrations