This is required to fix
```
adev/shared-docs/testing/testing-helper.ts💯12 - error TS2416: Property 'on' in type 'FakeWebContainer' is not assignable to the same property in base type 'WebContainer'.
Type '{ (event: "port", listener: PortListener): Unsubscribe; (event: "server-ready", listener: ServerReadyListener): Unsubscribe; (event: "error", listener: ErrorListener): Unsubscribe; (event: "preview-message", listener: PreviewMessageListener): Unsubscribe; }' is not assignable to type '{ (event: "port", listener: PortListener): Unsubscribe; (event: "server-ready", listener: ServerReadyListener): Unsubscribe; (event: "preview-message", listener: PreviewMessageListener): Unsubscribe; (event: "error", listener: ErrorListener): Unsubscribe; (event: "xdg-open", listener: OpenListener): Unsubscribe; (ev...'.
Types of parameters 'event' and 'event' are incompatible.
Type '"xdg-open"' is not assignable to type '"port"'.
100 override on(event: 'server-ready', listener: ServerReadyListener): Unsubscribe;
~~
```
See: https://github.com/angular/angular/actions/runs/14098789522/job/39491059550?pr=60526
PR Close#60581
To increase the ease of development we are moving @angular/docs into the adev directory within this repo. While
we are doing this to improve our development experience in the short term, efforts are also in place
to maintain a division between this @angular/docs (shared) code and adev itself, so that it can be extracted
back out in the future when components is ready to leverage it as well.
PR Close#57132
