fix(toggle): ensure proper visual selection when navigating via VoiceOver in Safari (#30349)

Issue number: resolves internal

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## What is the current behavior?
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Currently, MacOS voice over on Safari does not recognize ion-toggle
correctly and fails to highlight the element properly

## What is the new behavior?
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By adding the role property to the host element, we're correctly
identifying the toggle so Safari knows how to handle it.

## Does this introduce a breaking change?

- [ ] Yes
- [X] No

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## Other information

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