Issue #3568233: Add support for loading Drupal JavaScript libraries via custom elements
- Add attachment tracking to CustomElement class (getAttachments, setAttachments, addAttachments)
- Create DrupalLibraryElementGenerator service to generate drupal-library-* elements
- Library elements include resolved JS file paths with dependencies in correct load order
- Add kernel tests for attachment tracking and library element generation
Co-Authored-By: Claude Opus 4.5 noreply@anthropic.com
Closes #3568233
Edited by Ciprian Stavovei