fix(overlays): focus management with checkbox/radio (#30026)

Issue number: resolves internal

---------

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## What is the current behavior?
<!-- Please describe the current behavior that you are modifying. -->

Using `Tab` or `Shift + Tab` to focus through elements in a modal won't
behave as expected when using `ion-checkbox` or `ion-radio` within an
`ion-item`. Previously, the behavior would result in the last item in a
list getting focus styling, but `document.activeElement` would still be
the first actionable item in the overlay

## What is the new behavior?
<!-- Please describe the behavior or changes that are being added by
this PR. -->

For checkboxes, the `ion-checkbox` element itself will be focused rather
than the encapsulating `ion-item`

For radios, the `ion-radio-group` will be used to focus the appropriate
element. This will be the first `ion-radio` if there is no "checked"
item, or the "checked" item if one exists.

## Does this introduce a breaking change?

- [ ] Yes
- [x] No

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  2. Update the BREAKING.md file with the breaking change.
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## Other information

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

core/src/components.d.ts

@@ -2303,6 +2303,7 @@ export namespace Components {
           * The name of the control, which is submitted with the form data.
          */
         "name": string;
+        "setFocus": () => Promise<void>;
         /**
           * the value of the radio group.
          */

core/src/components/radio-group/radio-group.tsx

@@ -1,5 +1,5 @@
 import type { ComponentInterface, EventEmitter } from '@stencil/core';
-import { Component, Element, Event, Host, Listen, Prop, Watch, h } from '@stencil/core';
+import { Component, Element, Event, Host, Listen, Method, Prop, Watch, h } from '@stencil/core';
 import { renderHiddenInput } from '@utils/helpers';
 
 import { getIonMode } from '../../global/ionic-global';
@@ -217,6 +217,13 @@ export class RadioGroup implements ComponentInterface {
     }
   }
 
+  /** @internal */
+  @Method()
+  async setFocus() {
+    const radioToFocus = this.getRadios().find((r) => r.tabIndex !== -1);
+    radioToFocus?.setFocus();
+  }
+
   render() {
     const { label, labelId, el, name, value } = this;
     const mode = getIonMode(this);

core/src/utils/focus-trap.ts

@@ -13,7 +13,7 @@ import { focusVisibleElement } from '@utils/helpers';
  * valid usage for the disabled property on ion-button.
  */
 export const focusableQueryString =
-  '[tabindex]:not([tabindex^="-"]):not([hidden]):not([disabled]), input:not([type=hidden]):not([tabindex^="-"]):not([hidden]):not([disabled]), textarea:not([tabindex^="-"]):not([hidden]):not([disabled]), button:not([tabindex^="-"]):not([hidden]):not([disabled]), select:not([tabindex^="-"]):not([hidden]):not([disabled]), .ion-focusable:not([tabindex^="-"]):not([hidden]):not([disabled]), .ion-focusable[disabled="false"]:not([tabindex^="-"]):not([hidden])';
+  '[tabindex]:not([tabindex^="-"]):not([hidden]):not([disabled]), input:not([type=hidden]):not([tabindex^="-"]):not([hidden]):not([disabled]), textarea:not([tabindex^="-"]):not([hidden]):not([disabled]), button:not([tabindex^="-"]):not([hidden]):not([disabled]), select:not([tabindex^="-"]):not([hidden]):not([disabled]), ion-checkbox:not([tabindex^="-"]):not([hidden]):not([disabled]), ion-radio:not([tabindex^="-"]):not([hidden]):not([disabled]), .ion-focusable:not([tabindex^="-"]):not([hidden]):not([disabled]), .ion-focusable[disabled="false"]:not([tabindex^="-"]):not([hidden])';
 
 /**
  * Focuses the first descendant in a context
@@ -78,7 +78,13 @@ const focusElementInContext = <T extends HTMLElement>(
   }
 
   if (elementToFocus) {
+    const radioGroup = elementToFocus.closest('ion-radio-group');
+
+    if (radioGroup) {
+      radioGroup.setFocus();
+    } else {
       focusVisibleElement(elementToFocus);
+    }
   } else {
     // Focus fallback element instead of letting focus escape
     fallbackElement.focus();