fix(ci): run only server tests in Docker tester stage

Playwright Chromium is not available in node:24-alpine, causing the
vitest 'client' project (browser tests) to fail with an unhandled
browserType.launch error and exit code 1.

- Dockerfile: switch tester stage command to
  'npm run test:unit -- --run --project=server'
  so only Node.js unit tests run during Docker builds
- page.svelte.spec.ts: update stale 'renders h1' assertion to match
  the new InstaChef design (no h1; check for 'InstaChef' logo text)

Browser component tests still run locally when Playwright/Chromium
is available.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Dockerfile

@@ -4,7 +4,9 @@ WORKDIR /app
 COPY package*.json ./
 RUN npm ci
 COPY . .
-RUN npm test
+# Run only server-side unit tests; browser (Playwright) tests require a full
+# Chromium environment that is not available in the Alpine build stage.
+RUN npm run test:unit -- --run --project=server
 
 # ── stage: builder ───────────────────────────────────────────────────────────
 FROM node:24-alpine AS builder

src/routes/page.svelte.spec.ts

@@ -4,10 +4,11 @@ import { render } from 'vitest-browser-svelte';
 import Page from './+page.svelte';
 
 describe('/+page.svelte', () => {
-	it('should render h1', async () => {
+	it('should render the InstaChef app shell', async () => {
 		render(Page);
 
-		const heading = page.getByRole('heading', { level: 1 });
-		await expect.element(heading).toBeInTheDocument();
+		// The app logo text is the primary visible brand element in the TopBar
+		const logo = page.getByText('InstaChef');
+		await expect.element(logo).toBeInTheDocument();
 	});
 });