Improves input type definitions

[gburnett]

Fixes #

Improves ref and event handler types for Input and InnerInput.

Additional description

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REVIEWER checklist (do not remove)

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• [ ] Tests have been added for new props to prevent regressions in the future. See readme.
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[gburnett]

Checks are failing to install dependencies. I think that this is unrelated to my changes.

[interactivellama]

Looks better! Will try to get tests running.