src/vs/workbench/contrib/files/common/explorerModel.ts/ExplorerItem/hasChildren
class ExplorerItem:	hasChildren(filter: (stat: ExplorerItem) => boolean): boolean {
		if (this.hasNests) {
			return this.nestedChildren?.some(c => filter(c)) ?? false;
		} else {
			return this.isDirectory;
		}
	}