Add health check test for root endpoint

Author: DHANUSHGCODE

backend/tests/test_health.py

@@ -0,0 +1,9 @@
+from fastapi.testclient import TestClient
+from backend.main import app
+
+client = TestClient(app)
+
+def test_health_root():
+    resp = client.get("/")
+    assert resp.status_code == 200
+    assert "status" in resp.json() or resp.text != ""