[dagemawinegash]

Adds onFocus, onBlur, and onFocusChange to GridListItem for mouse and keyboard interaction, using the existing useFocus hook. Includes regression tests and an interactive Storybook example.

Part of #6460 (GridListItem only; table Row is outside this change).

✅ Pull Request Checklist:

• Included link to corresponding React Spectrum GitHub issue.
• Added unit tests and a Storybook example.
• Filled out test instructions.
• Updated documentation (if it already exists for this component).
• Looked at the ARIA grid practices.
• I understand every change in this PR and can explain why it's there.

API prop documentation derives from the inherited FocusEvents type; no separate documentation files were changed.

📝 Test Instructions:

1. Run yarn start and open React Aria Components → GridList → Item Focus Events.
2. Click different items, then use Tab and arrow keys. Verify the Actions panel reports focus, blur, and focus-change callbacks while selection and focus rings continue to work.
3. Run yarn test packages/react-aria-components/test/GridList.test.js --runInBand.

Validation: all 110 GridList tests, repository lint, and all 74 SSR tests passed (SSR used a 120-second local timeout). The full unit run had 16 failing tests and the browser run had two failures. All reproduced with the original GridList source: unit failures involve Windows locale/path handling and an interactive codemod fixture; browser failures involve TokenField word deletion in Chromium and Firefox.

🧢 Your Project:

Independent open-source contribution.