Expose registerHook and runHooks as official public APIs

[drewlee]

Addresses issue #1341. This change exposes registerHook, runHooks, and the associated types as official public API. The update essentially moves helper hooks out of -internal/ and modifies the associated imports.

- Verified addon builds and TS compiles properly.
- Tests pass.
- Verified hooks functionality and types via ember-a11y-testing.
- Verified published updates to API.md. See screenshot below.

[thegilby]

Thanks for upgrading these @drewlee!

Would it be helpful to update the API docs to include these?

[drewlee]

@thegilby Yeah, I'm following up with updates to the the API docs.

[drewlee]

Added usage info to API docs.

[drewlee]

@chriskrycho @scalvert

[chriskrycho]

This needs one set of changes (which you should be able to apply directly as a batch from the Files tab on this PR, if I’ve done things correctly here!) to account for a way the existing types misled you as you were working on this.

Thanks for getting this done!

[drewlee]

I incorporated the requested changes yesterday and updated the associated TSDoc comments so that things get published out properly to the API.md doc (see the screenshot in the PR description). I think this is good to go, would appreciate another look @chriskrycho. Thanks!

[simonihmig]

Thanks for getting this fixed! @chriskrycho may I ask you for a new release, so that we can get ember-a11y/ember-a11y-testing#498 unblocked? Thank you! 🙏

[chriskrycho]

@simonihmig sorry for the delay; let's get #1389 in as well early next week and get a release out!

[rwjblue]

As is, this will break any current users of ember-a11y-testing (and will require ember-a11y-testing to do a major release that only works with @ember/test-helpers@2.10.0 or whatever this PR is released as).

We should add the following (to this file) BEFORE releasing:

export function _registerHook(...args) {
  deprecate('something good here', { ... });
  return registerHook(...args);
}

export function _runHooks(...args) {
  deprecate('something good here', { ... });
  return runHooks(...args);
}

[MelSumner]

@rwjblue I think a new release of both will resolve the issue, yes? Coordinating a major version bump for this package now, and then it can be updated in ember-a11y-testing.

[chriskrycho]

@MelSumner we absolutely do not want to do a major of this right now. We have other TS things in flight which we want to land backwards-compatibly before that. This doesn't need a breaking change to release, it just needs a deprecation-and-not-removal here.