fix(sidebar): restore tree node collapsing

apps/desktop/src/lib/sidebar/sidebarTreeExpansion.ts

@@ -0,0 +1,9 @@
+import type { TreeNode } from "@/types/database";
+import { findSidebarActionTarget } from "@/lib/sidebar/sidebarActionTarget";
+
+export function syncSidebarTreeNodeExpansion(nodes: readonly TreeNode[], renderedNode: TreeNode): boolean {
+  const liveNode = findSidebarActionTarget(nodes, renderedNode);
+  if (!liveNode || liveNode === renderedNode || liveNode.isExpanded === renderedNode.isExpanded) return false;
+  liveNode.isExpanded = renderedNode.isExpanded;
+  return true;
+}