Fix visual regression issues with the media library and custom Vartheme Claro style for Layout Builder

Problem/Motivation

Reported internally by Yousef Bajawi (josebc)

• Missing vartheme-claro.theme.style.css file in latest varbase_layout_builder 10.0.38
• Reorder sections has issues

Follow up issue after
#3394143: Fix visual regressions issues with the off-canvas Claro under Drupal ~10.1.0 issues with Varbase Layout Builder and Layout Builder UX

Switched the compile of SCSS for that from gulp to webpack to support Gin and Claro in Drupal 10.
The vartheme-claro.theme.style.css file is a leftover with gulp

Proposed resolution

• Support legacy for off-canvas.theme for old Drupal 9 not upgraded yet sites.
• Add the custom fixes in Vartheme Claro styles back in the vartheme-claro.theme.style.css file
• Update the varbase_layout_builder/claro library to work for both Drupal 9 and Drupal 10

Remaining tasks

• ✅ File an issue about this project
• ✅ Addition/Change/Update/Fix to this project
• ✅ Testing to ensure no regression
• ➖ Automated unit/functional testing coverage
• ➖ Developer Documentation support on feature change/addition
• ➖ User Guide Documentation support on feature change/addition
• ➖ UX/UI designer responsibilities
• ➖ Accessibility and Readability
• ✅ Code review from 1 Varbase core team member
• ✅ Full testing and approval
• ✅ Credit contributors
• ✅ Review with the product owner
• ✅ Update Release Notes and Update Helper on new feature change/addition
• ✅ Release varbase-9.0.17, varbase_layout_builder-10.0.39

Varbase update type

• ✅ No Update
• ➖ Optional Update
• ➖ Forced Update
• ➖ Forced Update if Unchanged

User interface changes

• N/A

API changes

• N/A

Data model changes

• N/A

Release notes snippet

• Issue #3397497 by josebc: Fixed visual regression issues with the media library and custom Vartheme Claro style for Layout Builder