feat(textarea): added highlight and focus styles to ionic theme (#30062)

Issue number: internal

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

- Fixed highlight validation to include ionic theme
- Added styles on ionic scss partial for focus and highlight
- Added focus state test to textarea

## 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. -->

- Textarea [basic
sample](https://ionic-framework-git-rou-11444-ionic1.vercel.app/src/components/textarea/test/basic?ionic:theme=ionic)