test: remediate and stabilize auxiliary backend and frontend tests

- Standardized task log, LLM provider, and report profile tests.
- Relocated auxiliary tests into __tests__ directories for consistency.
- Updated git_service and defensive guards with minor stability fixes discovered during testing.
- Added UX integration tests for the reports list component.

backend/tests/core/test_defensive_guards.py

@@ -1,5 +1,6 @@
 import sys
 from pathlib import Path
+import shutil
 import pytest
 from unittest.mock import MagicMock
 
@@ -15,6 +16,17 @@ def test_git_service_get_repo_path_guard():
     with pytest.raises(ValueError, match="dashboard_id cannot be None"):
         service._get_repo_path(None)
 
+
+def test_git_service_get_repo_path_recreates_base_dir():
+    """Verify _get_repo_path recreates missing base directory before returning repo path."""
+    service = GitService(base_path="test_repos_runtime_recreate")
+    shutil.rmtree(service.base_path, ignore_errors=True)
+
+    repo_path = service._get_repo_path(42)
+
+    assert Path(service.base_path).is_dir()
+    assert repo_path == str(Path(service.base_path) / "42")
+
 def test_superset_client_import_dashboard_guard():
     """Verify that import_dashboard raises ValueError if file_name is None."""
     mock_env = Environment(