feat(frontend): Add View Transitions API with Framer Motion fallback (#113)

- Add framer-motion dependency for animation fallback
- Create useViewTransition hook for native View Transitions API
- Create view-transitions.css for CSS animations
- Update ResultCard with staggered blur-to-focus animation:
  - 75ms delay between cards
  - blur(10px) → blur(0px) effect
  - translateY(20px) → translateY(0) slide up
  - scale(0.98) → scale(1) subtle grow
- Wrap results list with AnimatePresence for exit animations
- Respect prefers-reduced-motion for accessibility

Fixes #113

Author: DevanshuNEU