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/tasks.css

@@ -61,7 +61,7 @@
   font-weight: var(--font-weight-medium);
   color: var(--color-text-secondary);
   transition: background-color var(--transition-fast), color var(--transition-fast);
-  min-height: unset;
+  min-height: var(--target-lg);
   cursor: pointer;
 }
 
@@ -265,7 +265,13 @@
   align-items: center;
   justify-content: center;
   transition: border-color var(--transition-fast), background-color var(--transition-fast);
-  min-height: unset;
+  position: relative;
+}
+
+.task-status-btn::before {
+  content: '';
+  position: absolute;
+  inset: -13px;
 }
 
 .task-status-btn--done {
@@ -433,7 +439,13 @@
   align-items: center;
   justify-content: center;
   transition: all var(--transition-fast);
-  min-height: unset;
+  position: relative;
+}
+
+.subtask-item__checkbox::before {
+  content: '';
+  position: absolute;
+  inset: -15px;
 }
 
 .subtask-item__checkbox--done {
@@ -463,7 +475,7 @@
   cursor: pointer;
   text-align: left;
   margin-top: var(--space-2);
-  min-height: unset;
+  min-height: var(--target-lg);
   transition: border-color var(--transition-fast), color var(--transition-fast);
 }