feat(navigation): Disable navigation elements when instances of HTMLButtonElement

[ettoredn]

Is your feature request related to a problem? Please describe.
I'd like to have navigation buttons disabled instead of only getting a class applied to them. Adding point-events: none to said class does cause the click/taps to "pass-through" to the element below. For instance, think a nav button over a thumbnails slider that when disabled would trigger a slide change on the main slider because the click passes through to the slide below it which, in turn, triggers the slide change on the main slider.

Describe the solution you'd like
Add an option to add disabled attribute to navigation elements when they are instances of HTMLButtonElement.

Describe alternatives you've considered
Adding point-events: none to the class results in the issues discussed above.

I've implemented the following custom module to obtain the desired effect.

import {Swiper} from "swiper";
import {SwiperComponent} from "swiper/types/shared";
import {NavigationOptions} from "swiper/types";

function updateButtons(swiper: Swiper) {
  if (!swiper.navigation)
    return;

  const params = swiper.params.navigation as NavigationOptions;

  if (swiper.navigation.prevEl instanceof HTMLButtonElement) {
    swiper.navigation.prevEl.disabled = swiper.navigation.prevEl.classList.contains(params.disabledClass as string);
  }
  if (swiper.navigation.nextEl instanceof HTMLButtonElement) {
    swiper.navigation.nextEl.disabled = swiper.navigation.nextEl.classList.contains(params.disabledClass as string);
  }
}

export default {
  name: 'navigation-disable-button',
  on: {
    init: updateButtons,
    toEdge: updateButtons,
    fromEdge: updateButtons,
  }
} as SwiperComponent;