Upgrade to StyleDictionary 4

[daneah]

The problem
We want our dependencies to be up to date so we can continue to benefit from and evolve with the ecosystem around us.

The solution
Upgrade from StyleDictionary 3 to 4

Additional information
See the official migration guidelines.

There are quite a few relevant breaking changes, as much of the breaking change footprint is around fairly commonly-used pieces. We make use of these in at least:

• packages/pharos/scripts/build-tokens.mjs
• packages/pharos/scripts/build-styles.js
• packages/pharos/style-dictionary.config.js

[Niznikr]

Would also recommend the DTCG format as you can start using features like composite tokens. Example PR.