fix(overlays): announce info after opening based on platform (#30025)

Issue number: internal

---------

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## What is the current behavior?
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PR https://github.com/ionic-team/ionic-framework/pull/29951 would hide
the overlays from screen readers while animating. This allows the
element to navigate to its correct destination for screen readers to
interact with. Otherwise, the focus rings would never appear. However,
this ended up breaking the interaction for iOS.

## What is the new behavior?
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this PR. -->

- Overlays are hidden from screen readers while animating only if the
platform is `android`. Since the original issue only applied to Android
devices.

## Does this introduce a breaking change?

- [ ] Yes
- [x] No

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## Other information

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screenshots of how the component looks before and after the change. -->

Dev build: `8.4.1-dev.11732033492.170e160c`

Test on iOS and Android devices.

core/src/utils/overlays.ts

@@ -32,6 +32,7 @@ import {
   removeEventListener,
 } from './helpers';
 import { printIonWarning } from './logging';
+import { isPlatform } from './platform';
 
 let lastOverlayIndex = 0;
 let lastId = 0;
@@ -973,18 +974,26 @@ export const createTriggerController = () => {
  * If the overlay is being presented, it prevents focus rings from appearing
  * in incorrect positions due to the transition (specifically `transform`
  * styles), ensuring that when aria-hidden is removed, the focus rings are
- * correctly displayed in the final location of the elements.
+ * correctly displayed in the final location of the elements. This only
+ * applies to Android devices.
+ *
+ * If this solution is applied to iOS devices, then it leads to a bug where
+ * the overlays cannot be accessed by screen readers. This is due to
+ * VoiceOver not being able to update the accessibility tree when the
+ * `aria-hidden` is removed.
  *
  * @param overlay - The overlay that is being animated.
  */
 const hideAnimatingOverlayFromScreenReaders = (overlay: HTMLIonOverlayElement) => {
   if (doc === undefined) return;
 
+  if (isPlatform('android')) {
     /**
      * Once the animation is complete, this attribute will be removed.
      * This is done at the end of the `present` method.
      */
     overlay.setAttribute('aria-hidden', 'true');
+  }
 };
 
 /**