🛠️ Configure testing setup and update Vitest configuration

code/websites/pokedex.online/tests/setup.js

@@ -0,0 +1,49 @@
+/**
+ * Test Setup File
+ * Runs before all tests to configure global test environment
+ */
+
+import { vi } from 'vitest';
+
+// Mock localStorage
+const localStorageMock = {
+  getItem: vi.fn(),
+  setItem: vi.fn(),
+  removeItem: vi.fn(),
+  clear: vi.fn()
+};
+global.localStorage = localStorageMock;
+
+// Mock sessionStorage
+const sessionStorageMock = {
+  getItem: vi.fn(),
+  setItem: vi.fn(),
+  removeItem: vi.fn(),
+  clear: vi.fn()
+};
+global.sessionStorage = sessionStorageMock;
+
+// Mock fetch
+global.fetch = vi.fn();
+
+// Mock console methods to reduce noise in tests
+global.console = {
+  ...console,
+  error: vi.fn(),
+  warn: vi.fn(),
+  log: vi.fn(),
+  debug: vi.fn()
+};
+
+// Reset all mocks before each test
+beforeEach(() => {
+  vi.clearAllMocks();
+  localStorageMock.getItem.mockReset();
+  localStorageMock.setItem.mockReset();
+  localStorageMock.removeItem.mockReset();
+  localStorageMock.clear.mockReset();
+  sessionStorageMock.getItem.mockReset();
+  sessionStorageMock.setItem.mockReset();
+  sessionStorageMock.removeItem.mockReset();
+  sessionStorageMock.clear.mockReset();
+});