Add Glint support

[danieljust]

This PR adds Glint support for element helper, so consumers will be able to

import type EmberElementHelperRegistry from 'ember-element-helper/template-registry';

declare module '@glint/environment-ember-loose/registry' {
  export default interface Registry extends EmberElementHelperRegistry { }
}

and {{element}} won't throw errors in hbs templates.

[SergeAstapov]

Suggested change

	import type EmberElementHelperRegistry from 'ember-css-modules/template-registry';
	import type EmberElementHelperRegistry from 'ember-element-helper/template-registry';

[SergeAstapov]

Suggested change

	"@glint/template": "1.0.0-beta.3"
	"@glint/template": "^1.0.0-beta.3"

[dfreeman]

Relying on private types for this is (a) dangerous, but (b) fortunately unnecessary 🙂

You can do this with public API and actually get the correct typing for it as well by defining the signature as something like:

export interface ElementHelperSignature<T extends string> {
  Args: {
    Positional: [name: T];
  };
  Return: ComponentLike<{
    Element: 
      T extends keyof HTMLElementTagNameMap
        ? HTMLElementTagNameMap[T]
        : Element;
    Blocks: { default: [] };
  }>;
}

export default class ElementHelper<T extends string> extends Helper<ElementHelperSignature<T>> {}

[NullVoxPopuli]

@danieljust thank you so much for your work! it was pulled in to #107 and we got it merged -- than kyou!!