feat(06-03): update display components to use categoryIcon with LucideIcon

- Rename categoryEmoji to categoryIcon in ItemCard, CandidateCard, ThreadCard, ItemPicker
- Import and render LucideIcon at appropriate sizes (36px placeholder, 14-16px badges)
- Update hook interfaces to match server API (categoryIcon instead of categoryEmoji)
- Rename iconData.ts to iconData.tsx (contains JSX)
- Update useCategories mutation type to use icon instead of emoji

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/client/hooks/useCategories.ts

@@ -29,7 +29,7 @@ export function useUpdateCategory() {
     }: {
       id: number;
       name?: string;
-      emoji?: string;
+      icon?: string;
     }) => apiPut<Category>(`/api/categories/${id}`, data),
     onSuccess: () => {
       queryClient.invalidateQueries({ queryKey: ["categories"] });

src/client/hooks/useItems.ts

@@ -14,7 +14,7 @@ interface ItemWithCategory {
   createdAt: string;
   updatedAt: string;
   categoryName: string;
-  categoryEmoji: string;
+  categoryIcon: string;
 }
 
 export function useItems() {

src/client/hooks/useSetups.ts

@@ -23,7 +23,7 @@ interface SetupItemWithCategory {
   createdAt: string;
   updatedAt: string;
   categoryName: string;
-  categoryEmoji: string;
+  categoryIcon: string;
 }
 
 interface SetupWithItems {

src/client/hooks/useThreads.ts

@@ -8,7 +8,7 @@ interface ThreadListItem {
   resolvedCandidateId: number | null;
   categoryId: number;
   categoryName: string;
-  categoryEmoji: string;
+  categoryIcon: string;
   createdAt: string;
   updatedAt: string;
   candidateCount: number;
@@ -29,7 +29,7 @@ interface CandidateWithCategory {
   createdAt: string;
   updatedAt: string;
   categoryName: string;
-  categoryEmoji: string;
+  categoryIcon: string;
 }
 
 interface ThreadWithCandidates {

src/client/hooks/useTotals.ts

@@ -4,7 +4,7 @@ import { apiGet } from "../lib/api";
 interface CategoryTotals {
   categoryId: number;
   categoryName: string;
-  categoryEmoji: string;
+  categoryIcon: string;
   totalWeight: number;
   totalCost: number;
   itemCount: number;