feat(settings): add autosave hint text below StaplesManager on D3 when ctx=settings

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

frontend/src/routes/household/staples/+page.svelte

@@ -50,5 +50,8 @@
 		{/if}
 		<h1 class="mb-[8px] font-[var(--font-display)] text-[18px] font-medium md:text-[28px] text-[var(--color-text)]">Vorräte</h1>
 		<StaplesManager categories={data.categories} context="settings" />
+		{#if data.ctx === 'settings'}
+			<p class="mt-4 font-[var(--font-sans)] text-[11px] text-[var(--color-text-muted)]">Änderungen werden automatisch gespeichert. Gilt ab der nächsten Einkaufsliste.</p>
+		{/if}
 	</div>
 {/if}

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

@@ -106,4 +106,29 @@ describe('staples page — ctx=settings (D3)', () => {
 		const backLink = screen.getByRole('link', { name: /← einstellungen/i });
 		expect(backLink).toHaveAttribute('href', '/settings');
 	});
+
+	it('renders hint text about autosave', () => {
+		render(Page, { props: { data: { categories: mockCategories, ctx: 'settings' } } });
+		expect(screen.getByText(/änderungen werden automatisch gespeichert/i)).toBeInTheDocument();
+	});
+
+	it('renders hint text about next shopping list', () => {
+		render(Page, { props: { data: { categories: mockCategories, ctx: 'settings' } } });
+		expect(screen.getByText(/gilt ab der nächsten einkaufsliste/i)).toBeInTheDocument();
+	});
+});
+
+describe('staples page — hint text absent in onboarding', () => {
+	beforeEach(() => {
+		vi.stubGlobal('fetch', vi.fn().mockResolvedValue({ ok: true }));
+	});
+
+	afterEach(() => {
+		vi.unstubAllGlobals();
+	});
+
+	it('does not render hint text in onboarding context', () => {
+		render(Page, { props: { data: { categories: mockCategories, ctx: 'onboarding' } } });
+		expect(screen.queryByText(/änderungen werden automatisch gespeichert/i)).not.toBeInTheDocument();
+	});
 });