Implement custom usables, regusterUsable

[NullVoxPopuli]

This is an important public API to formally support things like ember-modify-based-class-resource, as well as allow others to create usables in their libraries.

registerUsable is a very light wrapper around invokeHelper that allows customization of how args are pasesd to to the "helper"

For example, if ember-concurrency wanted to integrate with the usable system, they could do something like this:

import { macroCondition, dependencySatisfies, importSync } from '@embroider/macros';

if (macroCondition(dependencySatisfies('ember-resources', '>= 7.0.0'))) {
  const { registerUsable } = importSync('ember-resources');
  
  registerUsable('ember-concurrency', (context, config) => {
    const { args, definition } = config;
    return invokeHelper(context, definition, () => /* ... args ... */);
  });
}

Provided that:

• definition is registered with the helper-manager system.
• the config object has a type property with value set to ember-concurrency -- in practice this would be a property set on the result of their task function.

registerUsable is used in two places at the time of putting this PR up:

• in the function-based resource:

  registerUsable(TYPE, (context config) => {
    return invokeHelper(context, config);
  });

• in the class-based extracted addon, linked above:

  registerUsable(TYPE, (context, config) => {
    let { definition, thunk } = config;
  
    return invokeHelper(context, definition, () => normalizeThunk(thunk));
  });

---

This PR had a cascading affect which allowed the removal of some old Types that were previously only used for the class-based implementation.

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Estimated impact to a consuming app, depending on which bundle is imported

	js	min	min + gzip	min + brotli
/index.js	18.45 kB	4.39 kB	1.65 kB	1.45 kB

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Preview URLs

readme: https://d19c001f.ember-resources.pages.dev
api docs: https://d19c001f.ember-resources.pages.dev/modules.html