test(mobile): basic e2e tests (#8031)

fix AF-1289

1. tested on 'webkit'
2. a few baseline test cases

tests/affine-mobile/e2e/utils.ts

@@ -0,0 +1,15 @@
+/* eslint-disable unicorn/prefer-dom-node-dataset */
+import { expect, type Page } from '@playwright/test';
+
+export async function expandCollapsibleSection(page: Page, name: string) {
+  const divider = page.locator(`[data-collapsible]:has-text("${name}")`);
+  if ((await divider.getAttribute('data-collapsed')) === 'true') {
+    await divider.click();
+  }
+  await expect(divider).toHaveAttribute('data-collapsed', 'false');
+  const section = divider.locator(
+    '~ [data-testid="collapsible-section-content"]'
+  );
+  await expect(section).toBeVisible();
+  return section;
+}