feat: add `onKeyDown` prop to ListBoxItem for custom keyboard handling (#9181)
* Add `onKeyDown` prop to ListBoxItem for custom keyboard handling
* Update type annotation in ListBox example and fix style formatting in ListBox story
* fix: remove custom keyboard handling example from ListBox docs and story
* test: add unit tests for `onKeyDown` prop in ListBox component
* test: remove redundant assertions for `onKeyDown` in ListBox tests
* test: update `onKeyDown` tests in ListBox to use user-event for better simulation
* Add `onKeyDown` prop to ListBoxItem for custom keyboard handling
* Update type annotation in ListBox example and fix style formatting in ListBox story
* fix: remove custom keyboard handling example from ListBox docs and story
* test: add unit tests for `onKeyDown` prop in ListBox component
* test: remove redundant assertions for `onKeyDown` in ListBox tests
* test: update `onKeyDown` tests in ListBox to use user-event for better simulation
* chore: remove unnecessary blank lines in ListBox story
* chore: remove trailing blank line in ListBox story
* Add tests and move to useKeyboard
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Co-authored-by: Robert Snow <snowystinger@gmail.com>