Use name from file tree instead of calculating from path

extensions/ql-vscode/src/queries-panel/query-tree-data-provider.ts

@@ -39,6 +39,7 @@ export class QueryTreeDataProvider
     fileTreeDirectory: FileTreeNode,
   ): QueryTreeViewItem {
     return new QueryTreeViewItem(
+      fileTreeDirectory.name,
       fileTreeDirectory.path,
       fileTreeDirectory.children.map(this.convertFileTreeNode.bind(this)),
     );

extensions/ql-vscode/src/queries-panel/query-tree-view-item.ts

@@ -1,9 +1,12 @@
 import * as vscode from "vscode";
-import { basename } from "path";
 
 export class QueryTreeViewItem extends vscode.TreeItem {
-  constructor(path: string, public readonly children: QueryTreeViewItem[]) {
-    super(basename(path));
+  constructor(
+    name: string,
+    path: string,
+    public readonly children: QueryTreeViewItem[],
+  ) {
+    super(name);
     this.tooltip = path;
     this.collapsibleState = this.children.length
       ? vscode.TreeItemCollapsibleState.Collapsed