feat: Pre-populate version.content cache when getting version for c…

…ontent

djangocms_versioning/models.py

@@ -51,6 +51,7 @@ def get_for_content(self, content_object):
         version = self.get(
             object_id=content_object.pk, content_type__in=versionable.content_types
         )
+        version._state.fields_cache['content'] = content_object
         content_object._version_cache = version
         return version
 
@@ -243,8 +244,12 @@ def convert_to_proxy(self):
         """Returns a copy of current Version object, but as an instance
         of its correct proxy model"""
 
+        cache = self._state.fields_cache
+        del self._state.fields_cache  # Remove cache before creating deep copying
         new_obj = copy.deepcopy(self)
         new_obj.__class__ = self.versionable.version_model_proxy
+        new_obj._state.fields_cache = cache  # Recover caches
+        self._state.fields_cache = cache  # Recover caches
         return new_obj
 
     @property