fix: use onDragEnd on Reorder.Item instead of onPointerUp on Group

The previous approach used onPointerUp on the Reorder.Group which
fired unreliably — triggering on non-drag clicks and sometimes not
at all after a drag. Moving to onDragEnd on each Reorder.Item gives
clean, predictable drag-to-reorder behavior.

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

src/client/components/CandidateListItem.tsx

@@ -31,6 +31,7 @@ interface CandidateListItemProps {
 	isActive: boolean;
 	onStatusChange: (status: "researching" | "ordered" | "arrived") => void;
 	delta?: CandidateDelta;
+	onDragEnd?: () => void;
 }
 
 const RANK_COLORS = ["#D4AF37", "#C0C0C0", "#CD7F32"]; // gold, silver, bronze
@@ -53,6 +54,7 @@ export function CandidateListItem({
 	isActive,
 	onStatusChange,
 	delta,
+	onDragEnd,
 }: CandidateListItemProps) {
 	const controls = useDragControls();
 	const { weight, price } = useFormatters();
@@ -217,6 +219,7 @@ export function CandidateListItem({
 				value={candidate}
 				dragControls={controls}
 				dragListener={false}
+				onDragEnd={onDragEnd}
 				className={sharedClassName}
 			>
 				{innerContent}

src/client/routes/threads/$threadId.tsx

@@ -36,12 +36,11 @@ function ThreadDetailPage() {
 		thread?.categoryId ?? 0,
 	);
 
-	const [tempItems, setTempItems] =
-		useState<typeof thread extends { candidates: infer C } ? C : never | null>(
-			null,
-		);
+	const [tempItems, setTempItems] = useState<
+		NonNullable<typeof thread>["candidates"] | null
+	>(null);
 
-	// Clear tempItems when server data changes (biome-ignore: thread?.candidates is intentional dep)
+	// Clear tempItems when server data changes
 	// biome-ignore lint/correctness/useExhaustiveDependencies: thread?.candidates is the intended trigger
 	useEffect(() => {
 		setTempItems(null);
@@ -227,7 +226,6 @@ function ThreadDetailPage() {
 						axis="y"
 						values={displayItems}
 						onReorder={setTempItems}
-						onPointerUp={handleDragEnd}
 						className="flex flex-col gap-2"
 					>
 						{displayItems.map((candidate, index) => (
@@ -243,6 +241,7 @@ function ThreadDetailPage() {
 									})
 								}
 								delta={deltas[candidate.id]}
+								onDragEnd={handleDragEnd}
 							/>
 						))}
 					</Reorder.Group>