test: format test suite

tests/unit_tests/persistence/test_database_decorator.py

@@ -7,6 +7,7 @@ Tests cover:
 
 Note: Uses import isolation to break circular import chains.
 """
+
 from __future__ import annotations
 
 import sys
@@ -86,6 +87,7 @@ def get_database_module():
     """Get database module with import isolation."""
     with isolated_database_import():
         from langbot.pkg.persistence import database
+
         return database
 
 
@@ -198,4 +200,4 @@ class TestManagerClassDecorator:
         # Create instance to test method (with mock app)
         mock_app = Mock()
         instance = ManagerWithMethods(mock_app)
-        assert instance.custom_method() == 'test_value'
+        assert instance.custom_method() == 'test_value'

tests/unit_tests/persistence/test_mgr_methods.py

@@ -4,6 +4,7 @@ Tests cover:
 - execute_async() with mock database
 - get_db_engine() with mock database manager
 """
+
 from __future__ import annotations
 
 import pytest
@@ -85,7 +86,7 @@ class TestExecuteAsync:
         mock_db.get_engine = Mock(return_value=mock_engine)
         mgr.db = mock_db
 
-        result = await mgr.execute_async(sqlalchemy.text("SELECT 1"))
+        result = await mgr.execute_async(sqlalchemy.text('SELECT 1'))
 
         # Verify result is the same object returned by execute
         assert result is mock_result
@@ -152,4 +153,4 @@ class TestSerializeModelEdgeCases:
         result = mgr.serialize_model(SimpleModel, instance, masked_columns=['id', 'name'])
 
         # Result should be empty dict when all columns masked
-        assert result == {}
+        assert result == {}

tests/unit_tests/persistence/test_serialize_model.py

@@ -5,6 +5,7 @@ Tests cover:
 - datetime conversion to isoformat
 - masked_columns exclusion
 """
+
 from __future__ import annotations
 
 import datetime