{monaco-run} issue with importing angular

[johnnyelwailer]

Good day

I am having an issue with getting {monaco-run} to import certain packages.

```ts {monaco-run}
import { signal, effect } from '@angular/core';
import { TestBed } from '@angular/core/testing';
import { BrowserDynamicTestingModule, platformBrowserDynamicTesting } from '@angular/platform-browser-dynamic/testing';

TestBed.initTestEnvironment(BrowserDynamicTestingModule, platformBrowserDynamicTesting());
TestBed.runInInjectionContext(() => {
  const valueSignal = signal(1);
  console.log('Start');
  effect(() => {
    console.log('Signal:', valueSignal());
  });

  TestBed.flushEffects();
  console.log('After effect');
  valueSignal.set(1);
  TestBed.flushEffects(); 
  console.log('End');
});
```

I also tried simpler code:

I have also tried the frontmatter:

---
monacoRunAdditionalDeps:
 - '@angular/platform-browser-dynamic'
 - '@angular/core'
 - 'rxjs'
 - '@/snippets/angular-testbed'
---

The packages are all installed in package.json:

  "dependencies": {
    "@slidev/cli": "^51.7.1",
    "@slidev/theme-default": "latest",
    "@slidev/theme-seriph": "latest",
    "vue": "^3.5.14",
    "rxjs": "^7.8.2",
    "@angular/core": "19.2.13",
    "@angular/compiler": "19.2.13",
    "@angular/common": "19.2.13",
    "@angular/forms": "19.2.13",
    "@angular/platform-browser-dynamic": "19.2.13",
    "@angular/platform-browser": "19.2.13"
  }

Note that other code runs fine, for example this snippet works fine:

import { BehaviorSubject } from 'rxjs';

const subject = new BehaviorSubject(1);
console.log('Start');

subject.subscribe(value => {
  console.log('Observable:', value);
});

console.log('After subscribe');
subject.next(1);
console.log('End');

I am confused, as at some point I had '@angular/core' import actually working, but then another one failing to import.
I don't quite understand the problem, and what I am doing wrong.

Thanks in advance for any help!