test(staples): cover API failure fallback in page load

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

frontend/src/routes/household/staples/page.server.test.ts

@@ -84,4 +84,10 @@ describe('household staples page — load', () => {
 		expect(leer).toBeDefined();
 		expect(leer.ingredients).toHaveLength(0);
 	});
+
+	it('returns empty categories when API fails', async () => {
+		mockGet.mockResolvedValue({ data: undefined, error: { status: 500 } });
+		const result = await load({ fetch: vi.fn() } as any);
+		expect(result.categories).toEqual([]);
+	});
 });