a11y: Touch-Target System mit Token-basierter Sizing (Redesign Phase E)

- Neue Tokens: --target-sm (32px), --target-md (40px), --target-lg (48px)
- Globale min-height:44px Regel aus reset.css entfernt
- Alle 28 min-height:unset Overrides eliminiert
- Strategy A: Buttons, Nav-Items, Inputs → 48px mobile, 40px desktop
- Strategy B: Kleine Elemente (Checkboxen, Swatches, Delete-Buttons)
  → ::before Pseudo-Element expandiert Touch-Area auf 48×48px

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

public/styles/reset.css

@@ -59,11 +59,6 @@ h1, h2, h3, h4, h5, h6 {
   line-height: var(--line-height-tight);
 }
 
-/* Touch-Targets: Mindestgröße 44px */
-button, [role="button"], input[type="checkbox"], input[type="radio"] {
-  min-height: 44px;
-}
-
 /* Fokus-Styles (Accessibility) */
 :focus-visible {
   outline: 2px solid var(--color-accent);