style(AppTabbar): 调整App标签栏的水平内边距

优化标签栏布局间距，统一左右侧边内边距

@@ -59,7 +59,7 @@ const defaultIcon = 'fa-circle-o'
 const scrollHintStorageKey = 'app_tabbar_scroll_hint_seen_v1'
 const scrollHintOffset = 56
 const scrollableItemWidth = 168
-const scrollableSidePadding = 60
+const scrollableSidePadding = 48
 
 const tabbarStore = useTabbarStore()
 const tabItems = computed(() => tabbarStore.visibleTabItems)
@@ -226,7 +226,7 @@ onBeforeUnmount(() => {
   .app-tabbar__content {
     display: flex;
     align-items: stretch;
-    padding: 16rpx 28rpx 16rpx 52rpx;
+    padding: 16rpx 24rpx;
     box-sizing: border-box;
   }