test(web): add middleware + i18n + messages test suites (GOO-60)

Cover frontend middleware auth/locale logic, i18n config/routing/request/navigation,
and vi/en message parity — 91 new tests across 6 files.

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

apps/web/i18n/__tests__/navigation.spec.ts

@@ -0,0 +1,51 @@
+import { describe, expect, it, vi } from 'vitest';
+
+const { mockCreateNavigation } = vi.hoisted(() => ({
+  mockCreateNavigation: vi.fn(() => ({
+    Link: 'MockLink',
+    redirect: 'mockRedirect',
+    usePathname: 'mockUsePathname',
+    useRouter: 'mockUseRouter',
+  })),
+}));
+
+// Mock routing config
+vi.mock('../routing', () => ({
+  routing: {
+    locales: ['vi', 'en'] as const,
+    defaultLocale: 'vi',
+    localePrefix: 'as-needed',
+  },
+}));
+
+vi.mock('next-intl/navigation', () => ({
+  createNavigation: mockCreateNavigation,
+}));
+
+import { Link, redirect, usePathname, useRouter } from '../navigation';
+
+describe('i18n/navigation', () => {
+  it('calls createNavigation with the routing config', () => {
+    expect(mockCreateNavigation).toHaveBeenCalledWith({
+      locales: ['vi', 'en'],
+      defaultLocale: 'vi',
+      localePrefix: 'as-needed',
+    });
+  });
+
+  it('exports Link from createNavigation', () => {
+    expect(Link).toBeDefined();
+  });
+
+  it('exports redirect from createNavigation', () => {
+    expect(redirect).toBeDefined();
+  });
+
+  it('exports usePathname from createNavigation', () => {
+    expect(usePathname).toBeDefined();
+  });
+
+  it('exports useRouter from createNavigation', () => {
+    expect(useRouter).toBeDefined();
+  });
+});