Prevent users who can't add micronode content from accessing /node/add-microcontent

Problem/Motivation

The /node/add-microcontent route relies on the '_entity_create_any_access' => 'node' access check. As a result, users who have permission to create one or more regular node types, but no micronode types, are able to access the /node/add-microcontent route.

Once there, they are encouraged to create a new content type — something my test user is not authorized to do (which seems like a bug in Drupal\Core\EntityEntityCreateAnyAccessCheck?).

You have not created any content types yet. Go to the content type creation page to add a new content type.

Steps to reproduce

1. Create a user with the ability to add at least one regular node type.
2. Ensure that user does not have permission to create any micronode types.
3. Visit /node/add-microcontent.

Proposed resolution

• Extend AccessInterface to implement MicronodeCreateAnyAccessCheck.
• Update MicronodeRouteSubscriber to use new access check.