Introduce useEvent hook

[tsapeta]

Why

Introducing a hook that fires on event emitter's (e.g. native modules and shared objects) events and returns the event object of the most recently emitted event (or the initial value).

How

Added useEvent hook that uses addListener under the hood and re-renders whenever a new event comes in.

Test Plan

I tried to use the hook and the video player object and the event payload is property typed 👇 and updates whenever the source changes.

[expo-bot]

The Pull Request introduced fingerprint changes against the base commit: e7b39a6

Fingerprint diff

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Generated by PR labeler 🤖

[reichhartd]

Is the hook intended to standardise existing event listener hooks, such as useLowPowerMode in Expo Battery, and make it easier to enable new ones in packages (for example useClipboard)?

[tsapeta]

@reichhartd In the long-term, yes. For now the main purpose is to provide an API for hooks that will be used in shared objects, e.g. the video player from expo-video and the database in expo-sqlite.
Eventually, custom listener wrappers like addClipboardListener will also be replaced by NativeModule.addListener(...). What do you think about that?

[reichhartd]

@tsapeta Yep, sounds good and makes sense to replace the custom listener wrappers with a standardised method.
I asked because I was working on a draft for a function createEventEmitterHook a few weeks ago, and whether a similar function is also scope of this pull request.

[expo-bot]

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