chore: import upstream snapshot with attribution

packages/core/test-setup.ts

@@ -0,0 +1,59 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+// Unset NO_COLOR environment variable to ensure consistent theme behavior between local and CI test runs
+if (process.env.NO_COLOR !== undefined) {
+  delete process.env.NO_COLOR;
+}
+
+import { setSimulate429 } from './src/utils/testUtils.js';
+import { vi, afterEach } from 'vitest';
+import { coreEvents } from './src/utils/events.js';
+
+// Increase max listeners to avoid warnings in large test suites
+coreEvents.setMaxListeners(100);
+
+// Disable 429 simulation globally for all tests
+setSimulate429(false);
+
+afterEach(() => {
+  vi.unstubAllEnvs();
+});
+
+// Default mocks for Storage and ProjectRegistry to prevent disk access in most tests.
+// These can be overridden in specific tests using vi.unmock().
+
+vi.mock('./src/config/projectRegistry.js', async (importOriginal) => {
+  const actual =
+    await importOriginal<typeof import('./src/config/projectRegistry.js')>();
+  actual.ProjectRegistry.prototype.initialize = vi.fn(() =>
+    Promise.resolve(undefined),
+  );
+  actual.ProjectRegistry.prototype.getShortId = vi.fn(() =>
+    Promise.resolve('project-slug'),
+  );
+  return actual;
+});
+
+vi.mock('./src/config/storageMigration.js', async (importOriginal) => {
+  const actual =
+    await importOriginal<typeof import('./src/config/storageMigration.js')>();
+  actual.StorageMigration.migrateDirectory = vi.fn(() =>
+    Promise.resolve(undefined),
+  );
+  return actual;
+});
+
+vi.mock('./src/config/storage.js', async (importOriginal) => {
+  const actual =
+    await importOriginal<typeof import('./src/config/storage.js')>();
+  actual.Storage.prototype.initialize = vi.fn(() => Promise.resolve(undefined));
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
+  (actual.Storage.prototype as any).getProjectIdentifier = vi.fn(
+    () => 'project-slug',
+  );
+  return actual;
+});