fix(useHoverOverlay): Prevent React 19 act() console.error in tests

[sentry]

The issue JEST-2Y29 manifested as Error: Expected test not to call console.error(), specifically complaining about "An update to Tooltip inside a test was not wrapped in act(...)". This occurred because the useHoverOverlay hook's setTriggerElementRef callback directly called setTriggerElement (a useState setter) when the component was unmounted during test teardown. In React 19, state updates during unmount that happen outside act() boundaries trigger a console.error, which jest-fail-on-console then converts into a test failure.

The solution refactors how the triggerElement is managed:

1. A new useRef, triggerElementRef, is introduced to store the DOM element directly within the setTriggerElementRef callback.
2. A useLayoutEffect is added to synchronize the value from triggerElementRef.current to the triggerElement state. This useLayoutEffect runs during React's commit phase, which is always within an act() boundary in tests, thus preventing the console.error.
3. The useLayoutEffect intentionally has no dependency array to ensure it runs after every render, allowing it to catch ref updates. An internal guard (if (triggerElement !== triggerElementRef.current)) prevents infinite loops, and an eslint-disable-next-line comment is added to clarify this.

This change ensures that state updates related to the trigger element only occur within act() boundaries, resolving the test failures.

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Fixes JEST-2Y29

_{Comment @sentry <feedback> on this PR to have Autofix iterate on the changes.}

[ryan953]

duplicate of #120675