feat(ui): redesign GlobalSearchBar, split layouts, and remove hero section

- Make GlobalSearchBar functional with searchStore integration
- Add destination search using hubs/nodes GraphQL query
- Navigate to /request page instead of /catalog/offers
- Remove hero section from index.vue (search is now in header)
- Add padding (px-3 lg:px-6) to topnav layout
- Implement split layout for catalog pages (offers, hubs, suppliers)
  - Left side: filters + scrollable card list (40%)
  - Right side: map (60%, hidden on mobile)

app/layouts/topnav.vue

@@ -23,7 +23,7 @@
     <GlobalSearchBar v-if="showSearch" class="border-b border-base-300" />
 
     <!-- Page content -->
-    <main class="flex-1 flex flex-col min-h-0">
+    <main class="flex-1 flex flex-col min-h-0 px-3 lg:px-6">
       <slot />
     </main>
   </div>