refactor: replaced string refs with React.createRef across examples

[devesh760]

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Checklist

• The existing test suites (npm test) all pass
• For any new features or bug fixes, both positive and negative test cases have been added
• For any new features, documentation has been added (n/a)
• For any documentation changes, the text has been proofread and is clear to both experienced users and beginners
• Format your code with prettier (yarn run prettier)
• Run the Flow typechecks (yarn run typecheck)

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Description

This pull request removes the deprecated string refs and replaces them with React.createRef() across example files. String refs have been removed in React 19, so this update ensures compatibility with the latest version of React.

Changes Made:

• Updated ListExample to use React.createRef() instead of string refs for the List component.
• Updated TableExample to use React.createRef() instead of string refs for the Table component.
• Adjusted related bindings and state initializations to support React.createRef().
• Modified associated documentation to reflect these changes.

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Testing

• Verified that all existing test suites pass without errors.
• Manually tested the List and Table components to ensure they function as expected with the updated refs.

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Let me know if further adjustments are needed! 😊