Update dependencies and improve Python path handling

Updated several frontend dependencies including MUI packages and added new ones like `@mui/x-charts`. Adjusted the Python path setup in the CI configuration to correctly point to the `aaredb` backend, ensuring accurate module resolution.

backend/tests/test_auth.py

 # tests/test_auth.py
 
+import pytest
 from fastapi.testclient import TestClient
 from backend.main import app
 
-client = TestClient(app)
+
+@pytest.fixture(scope="module")
+def client():
+    with TestClient(app) as test_client:  # ensures lifespan/startup executes
+        yield test_client
 
 
 def test_login_success():