refactor: use shadow theme tokens, remove ProjectCard translate-hover

Replace inline var(--blue) arbitrary shadow values with typed theme
tokens (shadow-brutal-xl, shadow-brutal-2xl). Remove translate on
ProjectCard hover — shadow-only interaction is less distracting in
a dense grid layout.

src/entities/project/ui/ProjectCard/ProjectCard.test.tsx

@@ -41,7 +41,7 @@ describe('ProjectCard', () => {
     it('card has hover transition classes', () => {
       const { container } = render(<ProjectCard {...DEFAULT_PROPS} />);
       const card = container.firstChild as HTMLElement;
-      expect(card).toHaveClass('group', 'transition-all', 'duration-300');
+      expect(card).toHaveClass('group', 'transition-shadow', 'duration-300');
     });
 
     it('year badge has correct classes', () => {