test(geschichten): cover multi-person AND filter end-to-end

Adds a Playwright flow that picks two persons through the typeahead,
asserts both ?personId= params end up in the URL with two chips on
screen, then removes the first chip and verifies only the second
person id remains.

Also extends .prettierignore so a stale root-owned test-results
directory left over from running tests inside Docker doesn't break
the pre-commit lint hook.

frontend/.prettierignore

@@ -23,5 +23,6 @@ bun.lockb
 
 # Test artifacts
 /test-results/
+/test-results.locked/
 /e2e/.auth/
 /coverage/

frontend/e2e/geschichten.spec.ts

@@ -62,6 +62,51 @@ test.describe('Geschichten — writer + reader journey', () => {
 		await expect(page.locator('article')).toBeVisible();
 	});
 
+	test('multi-person filter: chips, URL params, and AND removal work end-to-end', async ({
+		page
+	}) => {
+		await page.goto('/geschichten');
+		await page.waitForSelector('[data-hydrated]');
+
+		// We need two persons to filter by. Open the picker and pick one whose name
+		// the dev seed reliably contains. Then open the picker again and pick a
+		// second one. Picking is via the typeahead — we type, wait for the listbox,
+		// click the first option.
+		async function pickPerson(query: string) {
+			await page.getByRole('button', { name: /Person wählen/ }).click();
+			const input = page.getByRole('combobox', { name: /Person wählen/ });
+			await input.fill(query);
+			// Wait for at least one option in the listbox, then click it
+			const firstOption = page.getByRole('option').first();
+			await expect(firstOption).toBeVisible();
+			await firstOption.click();
+		}
+
+		await pickPerson('a');
+		await page.waitForURL(/personId=/);
+		const firstUrl = new URL(page.url());
+		const firstIds = firstUrl.searchParams.getAll('personId');
+		expect(firstIds).toHaveLength(1);
+
+		await pickPerson('b');
+		await page.waitForURL((url) => url.searchParams.getAll('personId').length === 2);
+		const secondUrl = new URL(page.url());
+		const secondIds = secondUrl.searchParams.getAll('personId');
+		expect(secondIds).toHaveLength(2);
+		expect(secondIds[0]).toBe(firstIds[0]); // first one persists
+		expect(secondIds[1]).not.toBe(firstIds[0]); // second is different
+
+		// Two chips visible — find them by their remove-aria-label pattern
+		const chipButtons = page.getByRole('button', { name: /aus Filter entfernen/ });
+		await expect(chipButtons).toHaveCount(2);
+
+		// Remove the first chip — URL drops to one param
+		await chipButtons.first().click();
+		await page.waitForURL((url) => url.searchParams.getAll('personId').length === 1);
+		const finalIds = new URL(page.url()).searchParams.getAll('personId');
+		expect(finalIds).toEqual([secondIds[1]]);
+	});
+
 	test('AxeBuilder finds no critical violations on the index', async ({ page }) => {
 		await page.goto('/geschichten');
 		await page.waitForSelector('[data-hydrated]');