fix: resolve biome lint errors in discovery files

Remove unused functions and imports from route tests, fix array index key
warnings in skeleton components, apply biome formatting.

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

src/client/routes/index.tsx

@@ -143,12 +143,14 @@ function TrendingCategoriesSection() {
 			</div>
 			{isLoading ? (
 				<div className="flex flex-wrap gap-2">
-					{Array.from({ length: 8 }).map((_, i) => (
-						<div
-							key={i}
-							className="h-8 w-24 bg-gray-100 rounded-full animate-pulse"
-						/>
-					))}
+					{Array.from({ length: 8 }, (_, i) => `cat-skeleton-${i}`).map(
+						(key) => (
+							<div
+								key={key}
+								className="h-8 w-24 bg-gray-100 rounded-full animate-pulse"
+							/>
+						),
+					)}
 				</div>
 			) : (
 				<div className="flex flex-wrap gap-2">
@@ -172,9 +174,9 @@ function SectionSkeleton({ count, aspect }: { count: number; aspect: string }) {
 		<div
 			className={`grid ${aspect === "none" ? "grid-cols-1 sm:grid-cols-2 lg:grid-cols-3" : "grid-cols-2 sm:grid-cols-3 lg:grid-cols-4"} gap-4`}
 		>
-			{Array.from({ length: count }).map((_, i) => (
+			{Array.from({ length: count }, (_, i) => `skeleton-${i}`).map((key) => (
 				<div
-					key={i}
+					key={key}
 					className="bg-white rounded-xl border border-gray-100 overflow-hidden animate-pulse"
 				>
 					{aspect !== "none" && (