Add grid layout for catalog cards + hover shadow

- CatalogPage: added gridColumns prop (1/2/3 columns)
- Card: added hover:shadow-lg on interactive cards
- Products, hubs, suppliers pages now use 3-column grid
- Offers remain full-width (gridColumns=1 default)

app/pages/catalog/hubs/index.vue

@@ -3,6 +3,7 @@
     :items="displayItems"
     :map-items="itemsWithCoords"
     :loading="isLoading"
+    :grid-columns="3"
     with-map
     use-server-clustering
     map-id="hubs-map"

app/pages/catalog/offers/[productId]/index.vue

@@ -3,6 +3,7 @@
     :items="filteredHubs"
     :loading="isLoading"
     :total-count="hubs.length"
+    :grid-columns="3"
     with-map
     use-server-clustering
     cluster-node-type="logistics"

app/pages/catalog/offers/index.vue

@@ -3,6 +3,7 @@
     :items="filteredProducts"
     :loading="isLoading"
     :total-count="products.length"
+    :grid-columns="3"
     with-map
     use-server-clustering
     cluster-node-type="offer"

app/pages/catalog/suppliers/index.vue

@@ -3,6 +3,7 @@
     :items="displayItems"
     :map-items="itemsWithCoords"
     :loading="isLoading"
+    :grid-columns="3"
     with-map
     map-id="suppliers-map"
     point-color="#3b82f6"