Update Vite to 5.4 and Carbon to 1.63

Vite 5.4 natively supports `sass-embedded` so we no longer need to
install it aliased as `sass`. This simplifies things as we can rely
on dependabot to update it and avoid some issues with deduping the
dependency in the tree.

Although some packages, such as Carbon and Storybook, still reference
`sass` directly, Vite now prioritises `sass-embedded` if found.

As part of this update we also update Carbon and related packages
to remove remaining references to the aliased `sass-embedded` to
clean up the dependency tree.