Backport: Update 6.5.0

[cbravobernal]

What

Backports all changes from 6.5.0.

Needs testing before merging.

Changelog

Green ticks have been tested manually by me.

• Flexible Content layouts can now be renamed in the post editor, giving content editors better clarity when managing layouts ✅
• Flexible Content layouts can now be disabled, preventing them from rendering on the frontend without needing to delete their data ✅
• Flexible Content layouts can now be collapsed and expanded in bulk for faster content editing ✅
• Editing a Flexible Content layout now highlights the layout being edited, making it easier to identify ✅
• The Date and Date Time Picker fields can now be configured to default to the current date ✅
• Custom Icon Picker tabs now work correctly when used inside an ACF Block ✅
• Duplicating a Field Group no longer causes a fatal error when using Russian translations ✅
• ACF classes no longer use dynamic class properties, improving compatibility with PHP 8.2+ ✅
• Field group metabox collapse and expand buttons are no longer misaligned in the post editor ✅
• HTML is now escaped from field validation errors and tooltips ✅