refactor: add useFormatters hook to reduce boilerplate across 14 components

Created useFormatters() combining useWeightUnit + useCurrency + formatWeight/formatPrice
into a single hook returning weight(grams) and price(cents) bound functions plus
raw unit and currency values. Updated all 14 consumer files to use the new hook,
removing the repeated 4-import + 2-hook-call pattern from each.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/client/components/CandidateCard.tsx

@@ -1,6 +1,4 @@
-import { useCurrency } from "../hooks/useCurrency";
-import { useWeightUnit } from "../hooks/useWeightUnit";
-import { formatPrice, formatWeight } from "../lib/formatters";
+import { useFormatters } from "../hooks/useFormatters";
 import { LucideIcon } from "../lib/iconData";
 import { useUIStore } from "../stores/uiStore";
 import { RankBadge } from "./CandidateListItem";
@@ -41,8 +39,7 @@ export function CandidateCard({
 	cons,
 	rank,
 }: CandidateCardProps) {
-	const unit = useWeightUnit();
-	const currency = useCurrency();
+	const { weight, price } = useFormatters();
 	const openCandidateEditPanel = useUIStore((s) => s.openCandidateEditPanel);
 	const openConfirmDeleteCandidate = useUIStore(
 		(s) => s.openConfirmDeleteCandidate,
@@ -165,12 +162,12 @@ export function CandidateCard({
 					{rank != null && <RankBadge rank={rank} />}
 					{weightGrams != null && (
 						<span className="inline-flex items-center px-2 py-0.5 rounded-full text-xs font-medium bg-blue-50 text-blue-400">
-							{formatWeight(weightGrams, unit)}
+							{weight(weightGrams)}
 						</span>
 					)}
 					{priceCents != null && (
 						<span className="inline-flex items-center px-2 py-0.5 rounded-full text-xs font-medium bg-green-50 text-green-500">
-							{formatPrice(priceCents, currency)}
+							{price(priceCents)}
 						</span>
 					)}
 					<span className="inline-flex items-center px-2 py-0.5 rounded-full text-xs font-medium bg-gray-50 text-gray-600">