Add support for a11y_autocomplete widget

I've included the a11y_autocomplete_element module, I figured it fits best in the drupal_cms_accessibility_tools recipe.

The MR includes a #frontend-bundler-initiative alteration to the base project as a proof of concept for enabling automatic inclusion of JS dependencies without relying on any CDN. This only works if node exists on the runner or host where composer install is run.

I accept we may not want to make this a permanent part of the project, but I was encouraged to show how it could be done :)

To test:

1. ddev start
2. ddev drush si -y
3. ddev apply-recipe recipes/drupal_cms_accessibility_tools
4. go to https://drupal-cms-dev.ddev.site/admin/structure/types/manage/blog/form-... and select the Accessible autocomplete widget for the Tags field
5. create a Blog post and see the widget in action

Note that the CSS in the a11y_autocomplete_element is not yet compatible with the Gin theme.

A few questions...

Some answers :)

This needs 🐛 Import CSS in .mjs file Postponed for the CSS to work, which depends on #3472938: define CSS exports in package.json →

FWIW this would go in the base recipe, but doesn't matter too much right now.

#8 thanks, I didn't realise there was one. Moved.

This is currently blocked by 🐛 Import CSS in .mjs file Postponed which in turn is blocked by #3472938: define CSS exports in package.json →

If we can pull this off, it will be in the next minor version (v1.1.0) of Drupal CMS.

We might need to prod the maintainers of https://www.drupal.org/project/a11y_autocomplete →