Prosemirror rich text editing broke upon upgrade to Django 5.2

Plain textarea shown instead of rich text editor.

```
System check identified some issues:

WARNINGS:
edegal.Album.body: (django_prose_editor.W001) This ProseEditorField is using the legacy configuration format which is deprecated and will be removed in a future version. Add the 'extensions' configuration explicitly to use the new configuration format.
edegal.Album.body: (django_prose_editor.W004) This ProseEditorField doesn't have sanitization enabled. For security, it's recommended to enable sanitization.
HINT: Consider using the newer extensions mechanism with sanitize=True for proper HTML sanitization that matches your editor capabilities.
edegal.Photographer.body: (django_prose_editor.W001) This ProseEditorField is using the legacy configuration format which is deprecated and will be removed in a future version. Add the 'extensions' configuration explicitly to use the new configuration format.
edegal.Photographer.body: (django_prose_editor.W004) This ProseEditorField doesn't have sanitization enabled. For security, it's recommended to enable sanitization.
HINT: Consider using the newer extensions mechanism with sanitize=True for proper HTML sanitization that matches your editor capabilities.
edegal.Series.body: (django_prose_editor.W001) This ProseEditorField is using the legacy configuration format which is deprecated and will be removed in a future version. Add the 'extensions' configuration explicitly to use the new configuration format.
edegal.Series.body: (django_prose_editor.W004) This ProseEditorField doesn't have sanitization enabled. For security, it's recommended to enable sanitization.
HINT: Consider using the newer extensions mechanism with sanitize=True for proper HTML sanitization that matches your editor capabilities.
```