fix lap-bests distance matching + show PRs on activity page

frontend/src/pages/ActivityDetailPage.jsx

@@ -66,6 +66,12 @@ export default function ActivityDetailPage() {
     enabled: !!activity?.named_route_id,
   })
 
+  const { data: activityRecords } = useQuery({
+    queryKey: ['activity-records', id],
+    queryFn: () => api.get(`/activities/${id}/records`).then(r => r.data),
+    enabled: !!activity,
+  })
+
   const { data: routeBoard } = useQuery({
     queryKey: ['route-leaderboard', id],
     queryFn: () => api.get(`/activities/${id}/route-leaderboard`).then(r => r.data),
@@ -132,6 +138,21 @@ export default function ActivityDetailPage() {
         </div>
       </div>
 
+      {/* Personal records set in this activity */}
+      {activityRecords && activityRecords.length > 0 && (
+        <div className="flex flex-wrap items-center gap-2">
+          <span className="text-xs text-gray-500 mr-1">🏆 Personal best{activityRecords.length > 1 ? 's' : ''} set here:</span>
+          {activityRecords.map(pr => (
+            <span
+              key={pr.distance_label}
+              className="text-xs px-2.5 py-1 rounded-full bg-yellow-500/10 text-yellow-400 border border-yellow-500/30 font-medium"
+            >
+              {pr.distance_label} · {formatDuration(pr.duration_s)}
+            </span>
+          ))}
+        </div>
+      )}
+
       {/* Stats — all on one row */}
       <div className="grid grid-cols-2 sm:grid-cols-3 md:grid-cols-5 lg:grid-cols-10 gap-3">
         <StatCard label="Distance" value={formatDistance(activity.distance_m)} />