Implement unified catalog search with token-based filtering

- Add useCatalogSearch composable for managing unified search state
- Add UnifiedSearchBar component with token chips for filters
- Add CatalogHero component for empty/landing state
- Create grid components for each display mode:
  - CatalogGridProducts, CatalogGridSuppliers, CatalogGridHubs
  - CatalogGridHubsForProduct, CatalogGridProductsFromSupplier
  - CatalogGridProductsInHub, CatalogGridOffers
- Add unified catalog page at /catalog with query params
- Remove SubNavigation from catalog section (kept for other sections)
- Update all links to use new unified catalog paths
- Delete old nested catalog pages (offers/suppliers/hubs flows)
- Add i18n translations for catalog section

i18n/locales/ru/catalog.json

@@ -0,0 +1,36 @@
+{
+  "catalog": {
+    "filters": {
+      "product": "Товар",
+      "supplier": "Поставщик",
+      "hub": "Хаб",
+      "location": "Локация",
+      "quantity": "Количество"
+    },
+    "search": {
+      "placeholder": "Найти предложение...",
+      "searchProducts": "Поиск товаров...",
+      "searchSuppliers": "Поиск поставщиков...",
+      "searchHubs": "Поиск хабов..."
+    },
+    "hero": {
+      "title": "Найдите лучшее предложение",
+      "subtitle": "Выберите товар, поставщика или хаб для начала поиска"
+    },
+    "headers": {
+      "selectProduct": "Выберите товар",
+      "selectSupplier": "Выберите поставщика",
+      "selectHub": "Выберите хаб",
+      "hubsForProduct": "Хабы с товаром",
+      "productsFromSupplier": "Товары поставщика",
+      "productsInHub": "Товары в хабе",
+      "offers": "Предложения"
+    },
+    "empty": {
+      "noProducts": "Товары не найдены",
+      "noSuppliers": "Поставщики не найдены",
+      "noHubs": "Хабы не найдены",
+      "noOffers": "Предложения не найдены"
+    }
+  }
+}