fix: resolve flaky offline sync e2e test in CI

Playwright's setOffline(false) doesn't reliably emit the browser's
'online' DOM event in headless/CI environments. Manually dispatch it
as a safety net so the sync client always triggers.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

CLAUDE.md

@@ -180,6 +180,7 @@ Write tests first or alongside features. Tests serve as living documentation of
 - Test database: `./data/test-crumbs.db` (cleaned via `global-setup.ts`)
 - Auth fixture: `tests/e2e/helpers/fixtures.ts` provides `authenticatedPage` (handles setup/login race conditions across parallel workers)
 - Auth tests use `test.describe.serial` because they depend on sequential database state
+- **Offline/online tests**: After `setOffline(false)`, always manually dispatch the `online` event via `page.evaluate(() => window.dispatchEvent(new Event('online')))` — Playwright doesn't reliably emit it in headless/CI environments, causing flaky `waitForResponse` timeouts
 
 ### Gherkin-style Given/When/Then
 

tests/e2e/offline.spec.ts

@@ -62,8 +62,11 @@ test.describe('Offline Support', () => {
 		await expect(page.getByText('Survive Reload')).toBeVisible();
 
 		// When the network is restored and sync completes
-		const syncResponse = page.waitForResponse('**/api/sync');
+		const syncResponse = page.waitForResponse((resp) => resp.url().includes('/api/sync'));
 		await page.context().setOffline(false);
+		// Manually dispatch the online event as a safety net — in CI/headless
+		// environments, setOffline(false) doesn't always emit it reliably
+		await page.evaluate(() => window.dispatchEvent(new Event('online')));
 		await syncResponse;
 
 		// And the user reloads the page