Feature: #99092 - Allow static backdrops in modals

See forge#99092

Description

The Modal API is now able to render a static backdrop to avoid closing the modal when clicking it. This may be handy in case closing the modal would result in a negative user experience, e.g. in the image cropper.

Impact

The new boolean configuration option staticBackdrop controls whether a static backdrop should be rendered or not; the default is false.

Example:

import {default as Modal} from './modal';

Modal.advanced(
  title: 'Hello',
  content: 'This modal is not closable via clicking the backdrop.',
  size: Modal.sizes.small,
  staticBackdrop: true
);

Templates using the HTML class .t3js-modal-trigger to initialize a modal dialog can also use the new option by adding the data-static-backdrop attribute to the corresponding element.

Example:

<button class="btn btn-default t3js-modal-trigger"
    data-title="Hello"
    data-bs-content="This modal is not closable via clicking the backdrop."
    data-static-backdrop>
        Open modal
</button>