test(web): increase frontend test coverage to ~70% page coverage

- Fix vitest config to include [locale] directory tests (was excluded)
- Fix register.spec.tsx: use getByRole('heading') to avoid duplicate text match
- Fix search.spec.tsx: add QueryClientProvider wrapper and mock saved searches hook
- Add 12 new page test files covering dashboard, admin, public, and OAuth pages:
  - dashboard (main, profile, payments, subscription, KYC)
  - admin (dashboard, users)
  - public (landing, pricing)
  - analytics
  - OAuth callbacks (Google, Zalo)
- 29 test files, 174 tests, 16/23 pages covered (69.6%)

Co-Authored-By: Paperclip <noreply@paperclip.ing>

apps/web/app/[locale]/auth/callback/__tests__/google-callback.spec.tsx

@@ -0,0 +1,81 @@
+/* eslint-disable import-x/order */
+import { render, screen, waitFor } from '@testing-library/react';
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+import { useAuthStore } from '@/lib/auth-store';
+
+const mockReplace = vi.fn();
+let mockSearchParams = new URLSearchParams();
+
+vi.mock('next/navigation', () => ({
+  useRouter: () => ({ replace: mockReplace, push: vi.fn() }),
+  useSearchParams: () => mockSearchParams,
+}));
+
+vi.mock('lucide-react', () => ({
+  Loader2: ({ className }: { className?: string }) => <div data-testid="loader" className={className} />,
+}));
+
+vi.mock('@/lib/auth-store', () => {
+  const store = {
+    handleOAuthCallback: vi.fn(),
+  };
+  return {
+    useAuthStore: vi.fn((selector) => {
+      if (typeof selector === 'function') return selector(store);
+      return store;
+    }),
+  };
+});
+
+import GoogleCallbackPage from '../google/page';
+
+const mockedUseAuthStore = vi.mocked(useAuthStore);
+
+describe('GoogleCallbackPage', () => {
+  let mockStore: { handleOAuthCallback: ReturnType<typeof vi.fn> };
+
+  beforeEach(() => {
+    vi.clearAllMocks();
+    mockStore = {
+      handleOAuthCallback: vi.fn().mockResolvedValue(undefined),
+    };
+    mockedUseAuthStore.mockImplementation((selector) => {
+      if (typeof selector === 'function') return (selector as (s: typeof mockStore) => unknown)(mockStore);
+      return mockStore as ReturnType<typeof useAuthStore>;
+    });
+  });
+
+  it('renders loading spinner and text', () => {
+    mockSearchParams = new URLSearchParams();
+    render(<GoogleCallbackPage />);
+    expect(screen.getByTestId('loader')).toBeInTheDocument();
+    expect(screen.getByText(/đang xử lý đăng nhập google/i)).toBeInTheDocument();
+  });
+
+  it('redirects to login on error param', async () => {
+    mockSearchParams = new URLSearchParams('error=access_denied');
+    render(<GoogleCallbackPage />);
+
+    await waitFor(() => {
+      expect(mockReplace).toHaveBeenCalledWith('/login?error=access_denied');
+    });
+  });
+
+  it('redirects to login when tokens are missing', async () => {
+    mockSearchParams = new URLSearchParams();
+    render(<GoogleCallbackPage />);
+
+    await waitFor(() => {
+      expect(mockReplace).toHaveBeenCalledWith('/login?error=oauth_failed');
+    });
+  });
+
+  it('calls handleOAuthCallback with tokens', async () => {
+    mockSearchParams = new URLSearchParams('accessToken=abc&refreshToken=def&expiresIn=3600');
+    render(<GoogleCallbackPage />);
+
+    await waitFor(() => {
+      expect(mockStore.handleOAuthCallback).toHaveBeenCalledWith('abc', 'def', 3600);
+    });
+  });
+});

apps/web/app/[locale]/auth/callback/__tests__/zalo-callback.spec.tsx

@@ -0,0 +1,81 @@
+/* eslint-disable import-x/order */
+import { render, screen, waitFor } from '@testing-library/react';
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+import { useAuthStore } from '@/lib/auth-store';
+
+const mockReplace = vi.fn();
+let mockSearchParams = new URLSearchParams();
+
+vi.mock('next/navigation', () => ({
+  useRouter: () => ({ replace: mockReplace, push: vi.fn() }),
+  useSearchParams: () => mockSearchParams,
+}));
+
+vi.mock('lucide-react', () => ({
+  Loader2: ({ className }: { className?: string }) => <div data-testid="loader" className={className} />,
+}));
+
+vi.mock('@/lib/auth-store', () => {
+  const store = {
+    handleOAuthCallback: vi.fn(),
+  };
+  return {
+    useAuthStore: vi.fn((selector) => {
+      if (typeof selector === 'function') return selector(store);
+      return store;
+    }),
+  };
+});
+
+import ZaloCallbackPage from '../zalo/page';
+
+const mockedUseAuthStore = vi.mocked(useAuthStore);
+
+describe('ZaloCallbackPage', () => {
+  let mockStore: { handleOAuthCallback: ReturnType<typeof vi.fn> };
+
+  beforeEach(() => {
+    vi.clearAllMocks();
+    mockStore = {
+      handleOAuthCallback: vi.fn().mockResolvedValue(undefined),
+    };
+    mockedUseAuthStore.mockImplementation((selector) => {
+      if (typeof selector === 'function') return (selector as (s: typeof mockStore) => unknown)(mockStore);
+      return mockStore as ReturnType<typeof useAuthStore>;
+    });
+  });
+
+  it('renders loading spinner and Zalo text', () => {
+    mockSearchParams = new URLSearchParams();
+    render(<ZaloCallbackPage />);
+    expect(screen.getByTestId('loader')).toBeInTheDocument();
+    expect(screen.getByText(/đang xử lý đăng nhập zalo/i)).toBeInTheDocument();
+  });
+
+  it('redirects to login on error param', async () => {
+    mockSearchParams = new URLSearchParams('error=access_denied');
+    render(<ZaloCallbackPage />);
+
+    await waitFor(() => {
+      expect(mockReplace).toHaveBeenCalledWith('/login?error=access_denied');
+    });
+  });
+
+  it('redirects to login when tokens are missing', async () => {
+    mockSearchParams = new URLSearchParams();
+    render(<ZaloCallbackPage />);
+
+    await waitFor(() => {
+      expect(mockReplace).toHaveBeenCalledWith('/login?error=oauth_failed');
+    });
+  });
+
+  it('calls handleOAuthCallback with tokens', async () => {
+    mockSearchParams = new URLSearchParams('accessToken=zalo123&refreshToken=zaloref&expiresIn=1800');
+    render(<ZaloCallbackPage />);
+
+    await waitFor(() => {
+      expect(mockStore.handleOAuthCallback).toHaveBeenCalledWith('zalo123', 'zaloref', 1800);
+    });
+  });
+});