fix(Mixin): export MixinFactory type for ease of use

[johnjenkins]

What is the current behavior?

Devs have no steer regarding the typing of mixin factory functions for use with the new Mixin() utility

GitHub Issue Number: N/A

What is the new behavior?

The MixinFactory type has been exported for devs to use:

import { Method, Prop, type MixinFactory } from '@stencil/core';

export const WithMixinThing: MixinFactory = (Base) => {
  class MixinThing extends Base {
    @Prop() mixinThing = 'mixing ???';

    @Method()
    async mixinMethod() {
      console.log('Mixin method called');
      return 'Mixin method result';
    }
  }
  return MixinThing;
}

Documentation

Does this introduce a breaking change?

• Yes
• No

Testing

Other information