test: strengthen delete-permission include_deleted test to discriminate from other grants

test_delete_permission_with_include_deleted_for_trash_restore only checked
an owner and a fully-ungranted stranger, so it never proved perm=
actually discriminates delete_document from other permission grants. Add
a view_only user with view_document (but not delete_document) granted on
the same doc and assert they remain excluded, mirroring the pattern in
test_change_document_permission_is_distinct_from_view.

src/documents/tests/test_permission_filtering_security.py

@@ -244,7 +244,9 @@ class TestPermittedDocumentIdsArbitraryPermission:
     def test_delete_permission_with_include_deleted_for_trash_restore(self):
         owner = User.objects.create_user(username="owner")
         stranger = User.objects.create_user(username="mallory")
+        view_only = User.objects.create_user(username="viewer")
         doc = DocumentFactory(owner=owner)
+        assign_perm("view_document", view_only, doc)
         doc.delete()
 
         assert_visible_document_ids(
@@ -261,3 +263,12 @@ class TestPermittedDocumentIdsArbitraryPermission:
             expected_visible=[],
             expected_hidden=[doc.pk],
         )
+        assert_visible_document_ids(
+            permitted_document_ids(
+                view_only,
+                perm="delete_document",
+                include_deleted=True,
+            ),
+            expected_visible=[],
+            expected_hidden=[doc.pk],
+        )