Fix isort import ordering in SoftDeleteQuerySet.visible_to_user method

Reordered imports alphabetically within the visible_to_user method:
- django.apps comes before django.contrib.auth.models
- django.contrib.auth.models comes before django.db.models

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Co-Authored-By: Claude <[email protected]>
Co-authored-by: JSIV <[email protected]>

Author: 3 people

opencontractserver/conversations/models.py

@@ -53,8 +53,8 @@ def visible_to_user(self, user=None):
         Returns queryset filtered to objects visible to the user.
         Maintains soft-delete filtering from the base queryset.
         """
-        from django.contrib.auth.models import AnonymousUser
         from django.apps import apps
+        from django.contrib.auth.models import AnonymousUser
         from django.db.models import Q
 
         # Handle None user as anonymous