test(web/ui): add selector presence test for mobile navbar fix

Author: arvindm84

src/generators/web/ui/__tests__/index-css.test.mjs

@@ -0,0 +1,12 @@
+import assert from 'node:assert/strict';
+import { readFile } from 'node:fs/promises';
+import { join } from 'node:path';
+import { describe, it } from 'node:test';
+
+describe('web/ui/index.css', () => {
+  it('contains selector to hide empty hashed navItems container', async () => {
+    const cssPath = join(import.meta.dirname, '..', 'index.css');
+    const css = await readFile(cssPath, 'utf-8');
+    assert.ok(css.includes('div[class$="_navItems"]:empty'));
+  });
+});