docs(material/cdk/observers): Documentation supplement due to extended capabilities of the directive

[dananaprey]

When using the cdkObserveContent directive, I noticed that it reacts to changes in any content within the element it applies to, not just ng-content, or is this a coincidence?

If this is intended, I suggest improving the documentation so that this feature does not seem like a coincidence.
https://material.angular.dev/cdk/observers/overview

The suggested changes to the code could be edited better to convey the information more simply

Example:

<div class="content-wrapper" (click)="changeText()" (cdkObserveContent)="textChanged()">
  {{ text }}
</div>

text = 'text1';

textChanged() {
  console.log(this.text);
}

changeText() {
  this.text = 'text2';
}

When I click on the div in the console I see a message:

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