refactor(api): Update all modified files with dependency injection changes.

tests/conftest.py

@@ -126,6 +126,38 @@ def api_client(fastapi_app):
     return TestClient(fastapi_app)
 
 
+@pytest.fixture
+def mock_account_repo():
+    """Create mock AccountRepository for testing."""
+    from unittest.mock import MagicMock
+
+    return MagicMock()
+
+
+@pytest.fixture
+def mock_balance_repo():
+    """Create mock BalanceRepository for testing."""
+    from unittest.mock import MagicMock
+
+    return MagicMock()
+
+
+@pytest.fixture
+def mock_transaction_repo():
+    """Create mock TransactionRepository for testing."""
+    from unittest.mock import MagicMock
+
+    return MagicMock()
+
+
+@pytest.fixture
+def mock_analytics_proc():
+    """Create mock AnalyticsProcessor for testing."""
+    from unittest.mock import MagicMock
+
+    return MagicMock()
+
+
 @pytest.fixture
 def mock_db_path(temp_db_path):
     """Mock the database path to use temporary database for testing."""