fix(@angular/build): ensure test hooks are registered in non-headless browser mode

This commit moves the `beforeEach` and `afterEach` hook registrations for TestBed cleanup to be outside the global setup guard.

In non-headless browser environments, the setup file can be executed in different contexts where the global guard prevents the hooks from being registered, leading to inconsistent test behavior. This change ensures the cleanup hooks are always registered, improving reliability for headed browser test execution.

Due to the nature of the issue, which only manifests in headed browser mode, automated testing in a CI environment is problematic.

Author: clydin

packages/angular/build/src/builders/unit-test/runners/vitest/build-options.ts

@@ -36,6 +36,13 @@ function createTestBedInitVirtualFile(
     import { afterEach, beforeEach } from 'vitest';
     ${providersImport}
 
+    // The beforeEach and afterEach hooks are registered outside the globalThis guard.
+    // This ensures that the hooks are always applied, even in non-isolated browser environments
+    // where the setup file might be re-executed without re-initializing the global state.
+    // Same as https://github.com/angular/angular/blob/05a03d3f975771bb59c7eefd37c01fa127ee2229/packages/core/testing/srcs/test_hooks.ts#L21-L29
+    beforeEach(getCleanupHook(false));
+    afterEach(getCleanupHook(true));
+
     const ANGULAR_TESTBED_SETUP = Symbol.for('@angular/cli/testbed-setup');
     if (!globalThis[ANGULAR_TESTBED_SETUP]) {
       globalThis[ANGULAR_TESTBED_SETUP] = true;
@@ -44,10 +51,6 @@ function createTestBedInitVirtualFile(
       // In a non-isolated environment, this setup file can be executed multiple times.
       // The guard condition above ensures that the setup is only performed once.
 
-      // Same as https://github.com/angular/angular/blob/05a03d3f975771bb59c7eefd37c01fa127ee2229/packages/core/testing/srcs/test_hooks.ts#L21-L29
-      beforeEach(getCleanupHook(false));
-      afterEach(getCleanupHook(true));
-
       @NgModule({
         providers: [${usesZoneJS ? 'provideZoneChangeDetection(), ' : ''}...providers],
       })