feat: refine frontend folder management and display by merging folder tree data.

frontend/src/documents/features/selection/SelectionFloatingActions.tsx

@@ -238,9 +238,30 @@ const SelectionFloatingActions: React.FC<SelectionFloatingActionsProps> = ({
     () => foldersManager.getTreeSnapshot(),
   );
 
+  const dataSnapshot = useSyncExternalStore(
+    useCallback(cb => foldersManager.subscribe(cb), [foldersManager]),
+    () => foldersManager.getSnapshot(),
+    () => foldersManager.getSnapshot(),
+  );
+
   useEffect(() => {
-    setRemoteFolderTree(treeSnapshot);
-  }, [treeSnapshot]);
+    if (!treeSnapshot || treeSnapshot.length === 0) {
+      setRemoteFolderTree([]);
+      return;
+    }
+
+    const map = dataSnapshot;
+
+    const mergeNode = (node: FolderTreeNode): FolderTreeNode => {
+      const liveData = map.get(node.id);
+      const name = liveData?.name ?? node.name;
+      const children = node.children ? node.children.map(mergeNode) : [];
+      return { ...node, name, children };
+    };
+
+    const mergedTree = treeSnapshot.map(mergeNode);
+    setRemoteFolderTree(mergedTree);
+  }, [treeSnapshot, dataSnapshot]);
 
   const requestFolderTree = useCallback(() => {
     foldersManager.ensureTree();