[STORY] Design System Implementation

**Estimate**: 3 pts

## Acceptance Criteria
- Tailwind config with custom tokens
- Hard shadow utilities
- Color palette

Start by locating the Tailwind config and reviewing how the project currently defines theme values and utilities. Implement the custom tokens, hard shadow utilities, and color palette described in the acceptance criteria; done means all three are available through the design system and the project still builds successfully.

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