feat(17-03): update client components to use imageUrl from API responses

- Replace all /uploads/ path construction with imageUrl presigned URLs
- Add imageUrl prop to ItemCard, CandidateCard, CandidateListItem, ComparisonTable
- Update ImageUpload to use presigned URLs + local preview for new uploads
- Pass imageUrl through from parent components (CollectionView, forms, routes)

src/client/components/ItemCard.tsx

@@ -13,6 +13,7 @@ interface ItemCardProps {
 	categoryName: string;
 	categoryIcon: string;
 	imageFilename: string | null;
+	imageUrl?: string | null;
 	productUrl?: string | null;
 	onRemove?: () => void;
 	classification?: string;
@@ -28,6 +29,7 @@ export function ItemCard({
 	categoryName,
 	categoryIcon,
 	imageFilename,
+	imageUrl,
 	productUrl,
 	onRemove,
 	classification,
@@ -149,9 +151,9 @@ export function ItemCard({
 				</span>
 			)}
 			<div className="aspect-[4/3] bg-gray-50">
-				{imageFilename ? (
+				{imageUrl ? (
 					<img
-						src={`/uploads/${imageFilename}`}
+						src={imageUrl}
 						alt={name}
 						className="w-full h-full object-cover"
 					/>