Transform search bar in Quote mode to Airbnb-style segmented input

- Remove mode toggle [Explore/Quote] tabs from header
- In Quote mode: show segmented input (Product | Hub | Quantity) + Search button
- In Explore mode: keep regular pill input with chips
- Add productLabel, hubLabel, supplierLabel computed values to useCatalogSearch
- Pass Quote mode props to MainNavigation

app/composables/useCatalogSearch.ts

@@ -243,6 +243,11 @@ export function useCatalogSearch() {
     return !!(productId.value && (hubId.value || supplierId.value))
   })
 
+  // Labels for Quote mode display
+  const productLabel = computed(() => getLabel('product', productId.value))
+  const hubLabel = computed(() => getLabel('hub', hubId.value))
+  const supplierLabel = computed(() => getLabel('supplier', supplierId.value))
+
   return {
     // State
     selectMode,
@@ -262,6 +267,9 @@ export function useCatalogSearch() {
     activeTokens,
     availableChips,
     canSearch,
+    productLabel,
+    hubLabel,
+    supplierLabel,
 
     // Actions
     startSelect,