feat(api): ping route and testing infra

backend/tests/test_main.py

@@ -0,0 +1,15 @@
+import pytest
+from httpx import AsyncClient
+from starlette.testclient import TestClient
+
+from src.neo_neo_todo.main import app
+
+client = TestClient(app)
+
+
+@pytest.mark.anyio
+async def test_ping():
+    async with AsyncClient(app=app, base_url="http://test") as ac:
+        response = await ac.get("/control/ping")
+    assert response.status_code == 200
+    assert response.json() == {"ping": "pong"}