content: The IonSlides Angular migration guide should have "Notes" about the breaking change on Event handling

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Assessment

Difficulty
1/5
Estimated time
1-3 hours
Newbie friendliness
48/100
Issue type
Documentation
Clarity
Clearly specified
Activity status
Stale
Tech stack
angular
Domain
documentation

Research direction

Open the Angular migration guide at the documented slides Events section and compare its event-handling guidance with the linked Swiper Angular documentation. Add a note describing that Swiper events run outside NgZone and explain when ngZone.run or change detection is needed; done when the breaking change is clear in the guide.

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Description

content
URL

https://ionicframework.com/docs/angular/slides#events

Issue Description

When following the migration guide to switch using Swiper instead of IonSlides, I found one breaking change.
That is the triggered event is no longer part of NgZone.
This is also mentioned in the Swiper document.
https://swiperjs.com/angular#swiper-component-events

Note that Swiper Angular component all events emits outside of NgZone for better perfomance. Dont forget to use ngzone.run or ChangeDetector if you need to change view (e.g slides) in event handlers (e.g slideChange).

I think this should also be mentioned in the Ionic docs.

Below is a small sample:
In HTML, I put a testVariable both inside and outside of Swiper.

{{testVariable}}
  <swiper 
    [config]="config"
    (slideChangeTransitionEnd)="onSlideChange()">
    <ng-template swiperSlide>Slide1, {{testVariable}}</ng-template>
    <ng-template swiperSlide>Slide2 {{testVariable}}</ng-template>
    <ng-template swiperSlide>Slide3  {{testVariable}}</ng-template>
  </swiper>

In component code, if I don't surround the code with ngZone.run, only the testVariable inside Swiper is updating, the one outside of Swiper never changes. IonSlides doesn't have such behavior change.

  onSlideChange() {
    this.ngZone.run(() => {
      this.testVariable++;      
    });
  }
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