test: align unit stubs and fixtures with the review-round changes

CI caught three spots the targeted local runs missed: the relevance-path
unit tests still stubbed findAllById (the path now calls findByIdIn — the
batchMetadata stubs legitimately keep findAllById), the second
GeschichtenCard test file still expected the removed email fallback, and
the AND/OR-toggle describe lacked the wait-for-slide-transition guard its
sibling describe documents — the flake that failed run 2208.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

frontend/src/routes/SearchFilterBar.svelte.spec.ts

@@ -47,6 +47,10 @@ describe('SearchFilterBar – AND/OR tag operator toggle', () => {
 	async function openAdvanced() {
 		const filterBtn = page.getByRole('button', { name: 'Filter', exact: true });
 		await filterBtn.click();
+		// Wait for slide transition to finish before interacting with contents —
+		// clicking during the transition triggers track_reactivity_loss in Svelte 5 async.js
+		// (same guard as the undated-only describe below; this block flaked in CI run 2208).
+		await expect.element(page.getByTestId('undated-only-toggle')).toBeVisible();
 	}
 
 	it('hides AND/OR toggle when fewer than 2 tags are selected', async () => {