Rename SideMenu to NavMenu, fix tooltips, and update react-zen.

- Rename SideMenu to NavMenu with visible group title labels and selected item highlighting
- Update react-zen to 0.242.0 and fix responsive breakpoints (xs -> base)
- Style floating tooltips with inverted background across WorldMap, charts, and WeeklyTraffic
- Add CSS variables for primary color and use IconLabel consistently
- Remove stray console.log from LoadingPanel

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

src/app/(main)/websites/[websiteId]/WebsiteExpandedMenu.tsx

@@ -1,4 +1,4 @@
-import { SideMenu } from '@/components/common/SideMenu';
+import { NavMenu } from '@/components/common/NavMenu';
 import { useMessages, useNavigation } from '@/components/hooks';
 import {
   AppWindow,
@@ -226,5 +226,5 @@ export function WebsiteExpandedMenu({
     },
   ];
 
-  return <SideMenu items={items} selectedKey={view} onItemClick={onItemClick} />;
+  return <NavMenu items={items} selectedKey={view} onItemClick={onItemClick} />;
 }