feat: enhance E2E testing setup and model reporting

- Added a new fixture to manage runtime report artifacts in a writable temp directory during E2E tests, addressing permission issues in local CI/dev environments.
- Updated `conftest.py` to include a requirements.txt file in the model packaging path for training activities.
- Refactored existing fixtures to use `pytest.fixture` instead of `pytest_asyncio.fixture` for better compatibility.
- Enhanced the `Reports` class to include a target alias for report metrics, ensuring compatibility with Evidently's reporting requirements.
- Introduced new test scenarios to validate the handling of missing and whitespace-only `date_column` inputs in the training workflow.

These changes improve the robustness of the E2E testing framework and enhance the clarity of model reporting metrics.

tests/utils/repository/test_data_manager_repository.py

@@ -476,6 +476,35 @@ def test_generate_report_success(tmp_path):
             json.load(f)
 
 
+def test_generate_report_adds_target_alias_for_reports(tmp_path):
+    repo = dmr.DataManagerRepository(MagicMock())
+    p = TrainModelParams.from_dict(_minimal_dict_for_prepare())
+    tmr = TrainModelResult(
+        params=p,
+        train_data=pd.DataFrame({'v1': [1.0, 2.0], 't': [1.0, 2.0]}),
+        val_data=pd.DataFrame({'v1': [1.0, 2.0], 't': [1.0, 2.0]}),
+        y_train_pred=pd.DataFrame({'t': [1.0, 2.0]}),
+        y_pred=pd.DataFrame({'t': [1.0, 2.0]}),
+        run_name='testrun',
+    )
+
+    with (
+        patch.object(repo, '_get_reports_directory', return_value=str(tmp_path)),
+        patch('model_manager.utils.repository.data_manager_repository.Reports') as mrep,
+    ):
+        instance = mrep.return_value
+        instance.save_all_sections_html = Mock()
+        repo.generate_report(tmr, {})
+
+        kwargs = mrep.call_args.kwargs
+        reference_data = kwargs['reference_data']
+        current_data = kwargs['current_data']
+        assert 'target' in reference_data.columns
+        assert 'target' in current_data.columns
+        assert reference_data['target'].equals(reference_data['t'])
+        assert current_data['target'].equals(current_data['t'])
+
+
 def test_generate_report_skips_equation_file_when_not_linear(tmp_path):
     repo = dmr.DataManagerRepository(MagicMock())
     p = TrainModelParams.from_dict(_minimal_dict_for_prepare())