test(e2e): fix locators, add print assertion, cleanup, remove redundant emulateMedia

- help-popover: replace broad button[aria-expanded] with specific
  getByLabel('Lese- und Bearbeitungsmodus'); update role="tooltip" →
  role="region"; add afterAll doc cleanup (Sara/Tobias)
- richtlinien: assert .new-tab spans are hidden in print media — the
  existing test only checked .app-nav (Sara)
- transcribe-coach: remove 4× redundant page.emulateMedia({reducedMotion})
  calls — playwright.config.ts already sets reducedMotion: 'reduce' globally;
  add afterAll doc cleanup (Tobias)

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

frontend/e2e/help-popover.spec.ts

@@ -8,21 +8,27 @@ test.describe('Help chip — Read/Edit panel header', () => {
 		docId = await createEmptyDocument(request);
 	});
 
+	test.afterAll(async ({ request }) => {
+		await request.delete(`/api/documents/${docId}`);
+	});
+
 	test('opens popover on click, closes on Esc, returns focus to chip', async ({ page }) => {
 		await page.goto(`/documents/${docId}`);
 		await page.getByRole('button', { name: 'Transkribieren' }).click();
 
-		// Find and click the (?) help chip
-		const helpBtn = page.locator('button[aria-expanded]');
+		// Use the accessible label of the HelpPopover trigger (transcription_mode_help_label)
+		const helpBtn = page.getByRole('button', { name: 'Lese- und Bearbeitungsmodus' });
 		await expect(helpBtn).toBeVisible({ timeout: 5000 });
 		await helpBtn.click();
 
-		// Popover should open
-		await expect(page.locator('[role="tooltip"]')).toBeVisible();
+		// Popover should open (role="region", not tooltip — click-triggered panels are regions)
+		await expect(page.getByRole('region', { name: 'Lese- und Bearbeitungsmodus' })).toBeVisible();
 
 		// Press Esc
 		await page.keyboard.press('Escape');
-		await expect(page.locator('[role="tooltip"]')).not.toBeVisible();
+		await expect(
+			page.getByRole('region', { name: 'Lese- und Bearbeitungsmodus' })
+		).not.toBeVisible();
 
 		// Focus should have returned to the chip
 		await expect(helpBtn).toBeFocused();