feat(staples): add PATCH proxy server route for ingredient staple toggle

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

frontend/src/routes/household/staples/+server.ts

@@ -0,0 +1,24 @@
+import { json } from '@sveltejs/kit';
+import type { RequestHandler } from './$types';
+import { apiClient } from '$lib/server/api';
+
+export const PATCH: RequestHandler = async ({ request, fetch }) => {
+	const body = await request.json();
+	const { id, isStaple } = body;
+
+	if (!id) {
+		return json({ error: 'id is required' }, { status: 400 });
+	}
+
+	const api = apiClient(fetch);
+	const { error } = await api.PATCH('/v1/ingredients/{id}', {
+		params: { path: { id } },
+		body: { isStaple }
+	});
+
+	if (error) {
+		return json({ error: 'Failed to update ingredient' }, { status: 500 });
+	}
+
+	return new Response(null, { status: 204 });
+};

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

@@ -0,0 +1,63 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+
+vi.mock('$env/dynamic/private', () => ({
+	env: { BACKEND_URL: 'http://localhost:8080' }
+}));
+
+const mockPatch = vi.fn();
+vi.mock('$lib/server/api', () => ({
+	apiClient: () => ({ PATCH: mockPatch })
+}));
+
+describe('household staples PATCH handler', () => {
+	let PATCH: any;
+
+	beforeEach(async () => {
+		mockPatch.mockReset();
+		const mod = await import('./+server');
+		PATCH = mod.PATCH;
+	});
+
+	function createRequest(body: object) {
+		return {
+			request: {
+				json: () => Promise.resolve(body)
+			},
+			fetch: vi.fn()
+		} as any;
+	}
+
+	it('calls backend PATCH /v1/ingredients/{id} with isStaple', async () => {
+		mockPatch.mockResolvedValue({ data: {}, error: undefined });
+
+		await PATCH(createRequest({ id: 'ing-1', isStaple: true }));
+
+		expect(mockPatch).toHaveBeenCalledWith('/v1/ingredients/{id}', {
+			params: { path: { id: 'ing-1' } },
+			body: { isStaple: true }
+		});
+	});
+
+	it('returns 204 on success', async () => {
+		mockPatch.mockResolvedValue({ data: {}, error: undefined });
+
+		const response = await PATCH(createRequest({ id: 'ing-1', isStaple: true }));
+
+		expect(response.status).toBe(204);
+	});
+
+	it('returns 500 when backend returns an error', async () => {
+		mockPatch.mockResolvedValue({ data: undefined, error: { status: 500, message: 'error' } });
+
+		const response = await PATCH(createRequest({ id: 'ing-1', isStaple: false }));
+
+		expect(response.status).toBe(500);
+	});
+
+	it('returns 400 when id is missing', async () => {
+		const response = await PATCH(createRequest({ isStaple: true }));
+
+		expect(response.status).toBe(400);
+		expect(mockPatch).not.toHaveBeenCalled();
+	});
+});