[NPC] Sheet should have a better design

Feature Request

Short description of the proposed feature

The NPC sheet's first iteration looks pretty close to how it looks in books, but this causes it to stick out like a sore thumb when having multiple things opened (character sheet, item sheets, chat cards, etc.).

Proposed implementation

We should try to keep the Sourcebooks layout but refine the color scheme and design elements.

We should create an image prototype first to make sure we're all good on the new design and colors.

Reference

Encounters chapter in the Core Rulebook.