chore: vitest 4 for web, cli, and e2e (#26668)

web/src/test-data/setup.ts

@@ -3,19 +3,23 @@ import { init } from 'svelte-i18n';
 
 beforeAll(async () => {
   await init({ fallbackLocale: 'dev' });
-  Element.prototype.animate = vi.fn().mockImplementation(() => ({ cancel: () => {}, finished: Promise.resolve() }));
+  Element.prototype.animate = vi.fn().mockImplementation(function () {
+    return { cancel: () => {}, finished: Promise.resolve() };
+  });
 });
 
 Object.defineProperty(globalThis, 'matchMedia', {
   writable: true,
-  value: vi.fn().mockImplementation((query) => ({
-    matches: false,
-    media: query,
-    onchange: null,
-    addEventListener: vi.fn(),
-    removeEventListener: vi.fn(),
-    dispatchEvent: vi.fn(),
-  })),
+  value: vi.fn().mockImplementation(function (query) {
+    return {
+      matches: false,
+      media: query,
+      onchange: null,
+      addEventListener: vi.fn(),
+      removeEventListener: vi.fn(),
+      dispatchEvent: vi.fn(),
+    };
+  }),
 });
 
 vi.mock('$env/dynamic/public', () => {