fix: unify card styles across the project

- Set --bento-radius to 16px (was 24px) for more modern look
- Unified .card, .bento-card and Card component to use same:
  - border-radius: var(--bento-radius)
  - border: border-dark-700/40
  - background: bg-dark-900/70
  - inset shadow for glass effect
- Reduced padding from 24px to 20px

src/components/data-display/Card/Card.tsx

@@ -10,7 +10,7 @@ const cardVariants = cva(
   [
     'relative overflow-hidden',
     'border border-dark-700/40 bg-dark-900/70',
-    'rounded-linear-lg',
+    'rounded-[var(--bento-radius)]',
     'transition-all duration-200',
     // GPU acceleration
     'transform-gpu',