Configurable CSS classes for Annotation field wrapper in admin settings
- New field "Annotation field CSS classes" in Annotation Field Settings section
- Fixes overlap issue between annotation textarea and signature checkbox in Bootstrap themes
- Classes applied via `#wrapper_attributes` to the field container (not the textarea itself)
Use Cases
- Bootstrap themes: Use "mt-3 col-12" or "clearfix mt-2" to fix layout
- Overlap fix: "d-block w-100 mt-3" forces annotation below the checkbox
- Custom themes: Any custom classes for layout control