FR (Angular Authenticator): Ability to override confirm signin to use recaptcha

### Before creating a new issue, please confirm:

- [X] I have [searched for duplicate or closed issues](https://github.com/aws-amplify/amplify-ui/issues?q=is%3Aissue+) and [discussions](https://github.com/aws-amplify/amplify-ui/discussions).
- [X] I have tried disabling all browser extensions or using a different browser
- [X] I have tried deleting the node_modules folder and reinstalling my dependencies
- [X] I have read the guide for [submitting bug reports](https://github.com/aws-amplify/amplify-ui/blob/main/CONTRIBUTING.md#bug-reports).

### On which framework/platform are you having an issue?

Angular

### Which UI component?

Authenticator

### How is your app built?

"@aws-amplify/ui-angular": "^3.2.11",

### What browsers are you seeing the problem on?

Chrome

### Please describe your bug.

The documentation for angular in the [angular chapter custom-auth-challenge-with-google-recaptcha](https://docs.amplify.aws/cli/usage/lambda-triggers/#custom-auth-challenge-with-google-recaptcha) is only working with the obsolete version of aws-amplify-angular, and I cannot find a working solution with @aws-amplify/ui-angular.
Also the [frontend documentation (ui.docs.amplify.aws/angular)](https://ui.docs.amplify.aws/angular/connected-components/authenticator/customization) is not handling the setup for google recpatcha.

The VerifyAuthChallenge is configured with the secret key of Recaptcha, but I don't know how to include the site key/recaptcha compenent in the existing amplify-authenticator.

### What's the expected behaviour?

Working Solution for using Google Recaptcha within the Amplify Authenticator module in Angular.

### Help us reproduce the bug!

It's a documentation issue.

### Code Snippet

Following solution is not working, as auth.confirmSignIn cannot be filled and auth.submitSignIn is also missing from [angular chapter custom-auth-challenge-with-google-recaptcha](https://docs.amplify.aws/cli/usage/lambda-triggers/#custom-auth-challenge-with-google-recaptcha) MAybe the correct amplifySlot can help here.
```html

```

### Additional information and screenshots

_No response_

Start by comparing the linked CLI custom-auth-challenge-with-google-recaptcha chapter with the Angular Authenticator customization documentation and the reported @aws-amplify/ui-angular API. Verify how the Angular Authenticator exposes the confirm-sign-in step and recaptcha site key, then update the relevant documentation with a working setup and example.

Written by the indexing model from the issue text.