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/richtlinien.spec.ts

@@ -63,6 +63,12 @@ test.describe('Richtlinien page — print media', () => {
 			await expect(nav).toBeHidden();
 		}
 
+		// .new-tab annotation spans must be hidden in print so "(öffnet in neuem Tab)"
+		// text does not clutter the printed output (the print CSS declares display:none)
+		for (const span of await page.locator('.new-tab').all()) {
+			await expect(span).toBeHidden();
+		}
+
 		await page.screenshot({ path: 'test-results/e2e/richtlinien-print.png', fullPage: true });
 	});
 });