feat(map): manage agent overlays in layer panel

src/features/map/core/components/layer-panel.tsx

@@ -46,17 +46,10 @@ type LayerVisibilitySectionProps = {
 
 function LayerVisibilitySection({ items, onToggleLayer }: LayerVisibilitySectionProps) {
   const groups = groupLayerItems(items);
-  const [openGroupIds, setOpenGroupIds] = useState(
-    () => new Set(groups.filter((group) => group.defaultOpen).map((group) => group.id))
-  );
+  const [groupOpenStates, setGroupOpenStates] = useState<Record<string, boolean>>({});
 
   const handleGroupToggle = (groupId: string, open: boolean) => {
-    setOpenGroupIds((current) => {
-      const next = new Set(current);
-      if (open) next.add(groupId);
-      else next.delete(groupId);
-      return next;
-    });
+    setGroupOpenStates((current) => ({ ...current, [groupId]: open }));
   };
 
   return (
@@ -64,7 +57,7 @@ function LayerVisibilitySection({ items, onToggleLayer }: LayerVisibilitySection
       {groups.map((group) => (
         <details
           key={group.id}
-          open={openGroupIds.has(group.id)}
+          open={groupOpenStates[group.id] ?? group.defaultOpen}
           onToggle={(event) => handleGroupToggle(group.id, event.currentTarget.open)}
           className="surface-well group/layer overflow-hidden rounded-xl border"
         >