💫 feat(shell-tabs): add subtle animation for active tab

- Add scale pulse animation when tab becomes active
- Respect prefers-reduced-motion for accessibility
- Prevent animation during fade-slide-out transitions

libs/shell/tabs/src/lib/components/shell-tab-item.component.css

@@ -2,8 +2,32 @@
   @apply block opacity-40 self-end;
 }
 
-:host.active {
+:host.active:not(.fade-slide-out) {
   @apply opacity-100;
+  animation: tabActivate 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
+}
+
+:host.active.fade-slide-out {
+  @apply opacity-100;
+}
+
+/* Active tab animation - subtle scale pulse */
+@keyframes tabActivate {
+  0% {
+    transform: scale(1);
+  }
+  50% {
+    transform: scale(1.03);
+  }
+  100% {
+    transform: scale(1);
+  }
+}
+
+@media (prefers-reduced-motion: reduce) {
+  :host.active:not(.fade-slide-out) {
+    animation: none;
+  }
 }
 
 a {