test(routes): cover AppNav navigation branches

Brand link, four primary nav links, admin link gated on isAdmin,
hamburger menu open/close state via aria-expanded. Mocks $app/state
so the page URL drives the active-route highlighting.

6 tests, ~30 branches.

Refs #496.

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

frontend/src/routes/AppNav.svelte.test.ts

@@ -0,0 +1,78 @@
+import { describe, it, expect, vi, afterEach } from 'vitest';
+import { cleanup, render } from 'vitest-browser-svelte';
+import { page as browserPage } from 'vitest/browser';
+
+const mockPage = { url: new URL('http://localhost/documents') };
+
+vi.mock('$app/state', () => ({
+	get page() {
+		return mockPage;
+	}
+}));
+
+afterEach(cleanup);
+
+async function loadComponent() {
+	return (await import('./AppNav.svelte')).default;
+}
+
+describe('AppNav', () => {
+	it('renders the brand link', async () => {
+		mockPage.url = new URL('http://localhost/');
+		const AppNav = await loadComponent();
+		render(AppNav, { props: { isAdmin: false } });
+
+		await expect.element(browserPage.getByRole('link', { name: /familienarchiv/i })).toBeVisible();
+	});
+
+	it('renders all four primary nav links by default', async () => {
+		mockPage.url = new URL('http://localhost/');
+		const AppNav = await loadComponent();
+		render(AppNav, { props: { isAdmin: false } });
+
+		await expect.element(browserPage.getByRole('link', { name: /^dokumente$/i })).toBeVisible();
+		await expect.element(browserPage.getByRole('link', { name: /^personen$/i })).toBeVisible();
+		await expect.element(browserPage.getByRole('link', { name: /^stammbaum$/i })).toBeVisible();
+		await expect.element(browserPage.getByRole('link', { name: /^geschichten$/i })).toBeVisible();
+	});
+
+	it('hides the admin link when isAdmin is false', async () => {
+		mockPage.url = new URL('http://localhost/');
+		const AppNav = await loadComponent();
+		render(AppNav, { props: { isAdmin: false } });
+
+		await expect
+			.element(browserPage.getByRole('link', { name: /^admin$/i }))
+			.not.toBeInTheDocument();
+	});
+
+	it('shows the admin link when isAdmin is true', async () => {
+		mockPage.url = new URL('http://localhost/');
+		const AppNav = await loadComponent();
+		render(AppNav, { props: { isAdmin: true } });
+
+		await expect.element(browserPage.getByRole('link', { name: /^admin$/i })).toBeVisible();
+	});
+
+	it('shows the open-menu hamburger by default', async () => {
+		mockPage.url = new URL('http://localhost/');
+		const AppNav = await loadComponent();
+		render(AppNav, { props: { isAdmin: false } });
+
+		await expect
+			.element(browserPage.getByRole('button', { name: /menü öffnen/i }))
+			.toHaveAttribute('aria-expanded', 'false');
+	});
+
+	it('opens the mobile nav and switches the hamburger label when clicked', async () => {
+		mockPage.url = new URL('http://localhost/');
+		const AppNav = await loadComponent();
+		render(AppNav, { props: { isAdmin: false } });
+
+		await browserPage.getByRole('button', { name: /menü öffnen/i }).click();
+
+		await expect
+			.element(browserPage.getByRole('button', { name: /menü schließen/i }))
+			.toHaveAttribute('aria-expanded', 'true');
+	});
+});