add EventFromStore utility type to @xstate/store

[with-heart]

This PR adds the EventFromStore utility type to @xstate/store. EventFromStore allows us to extract the type of events from a given store:

import { createStore, type EventFromStore } from '@xstate/store';

const store = createStore(
  { count: 0 },
  {
    add: (context, event: { addend: number }) => ({
      count: context.count + event.addend
    }),
    multiply: (context, event: { multiplier: number }) => ({
      count: context.count * event.multiplier
    })
  }
);

type StoreEvent = EventFromStore<typeof store>;
//   ^? { type: 'add'; addend: number } | { type: 'multiply'; multiplier: number }

This idea came about thanks to @qiushiyan in #5017.

[changeset-bot]

🦋 Changeset detected

Latest commit: ffc1973

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@xstate/store	Minor

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