feat(frontend): add v2 design system tokens

- Premium dark theme with near-black background (#09090b)
- Indigo accent color (#6366f1) for intelligence/premium feel
- Glassmorphism tokens for blur effects and glass cards
- Animation tokens with expo easing and stagger delays
- Typography scale with Inter + JetBrains Mono
- Shadcn/ui compatibility maintained
- TypeScript constants for JS usage

Closes #110

Author: DevanshuNEU