refactor(searchbar): update according to design (#30245)

Issue number: internal

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## What is the current behavior?
The searchbar component does not currently match our UX designs for the
ionic theme.

## What is the new behavior?
Updated the searchbar so that it does:
- Adjusted the searchbar input paddings when no leading or trailing
icons are rendered;
- Added an ellipsis text overflow to the searchbar input;
- Updated the background, text and icon colors so that they are reactive
to state changes like having inserted text and being disabled (some
design tokens are still TBD);
- The clear button is now hidden when the searchbar is disabled.

## 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. -->

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Co-authored-by: Maria Hutt <thetaPC@users.noreply.github.com>