test: add agent test coverage and standardize test suite (#2051)

- Add 104 comprehensive tests for agent system
- Integrate agent tests into CI/CD pipeline
- Standardize tests with @pytest.mark.unit markers
- Fix cross-platform path compatibility
- Clean up unused imports and dependencies

tests/test_celery.py

@@ -1,21 +1,21 @@
 from unittest.mock import patch
-from application.core.settings import settings
+
+import pytest
 from application.celery_init import make_celery
+from application.core.settings import settings
 
 
-@patch('application.celery_init.Celery')
+@pytest.mark.unit
+@patch("application.celery_init.Celery")
 def test_make_celery(mock_celery):
-    # Arrange
-    app_name = 'test_app_name'
+    app_name = "test_app_name"
 
-    # Act
     celery = make_celery(app_name)
 
-    # Assert
     mock_celery.assert_called_once_with(
-        app_name, 
-        broker=settings.CELERY_BROKER_URL, 
-        backend=settings.CELERY_RESULT_BACKEND
+        app_name,
+        broker=settings.CELERY_BROKER_URL,
+        backend=settings.CELERY_RESULT_BACKEND,
     )
     celery.conf.update.assert_called_once_with(settings)
-    assert celery == mock_celery.return_value
+    assert celery == mock_celery.return_value