fix(sidebar): 修复侧边栏树状态显示

src/lib/sidebarTreeItemLayout.ts

@@ -0,0 +1,28 @@
+import type { TreeNodeType } from "@/types/database";
+
+const leafTypes: Set<TreeNodeType> = new Set([
+  "column",
+  "index",
+  "fkey",
+  "trigger",
+  "object-browser",
+  "redis-db",
+  "mongo-collection",
+  "saved-sql-file",
+]);
+
+export function treeItemPaddingLeft(depth: number): string {
+  return `${depth * 16 + 8}px`;
+}
+
+export function canTreeNodeExpand(type: TreeNodeType): boolean {
+  return !leafTypes.has(type);
+}
+
+export function canTreeNodeShowExpander({ type, childCount }: { type: TreeNodeType; childCount?: number }): boolean {
+  if (!canTreeNodeExpand(type)) return false;
+  if (type === "saved-sql-root" || type === "saved-sql-folder") {
+    return (childCount ?? 0) > 0;
+  }
+  return true;
+}