Add SystemTest Agent and Controller

SystemTest-Agent/app/state.py

@@ -0,0 +1,20 @@
+from __future__ import annotations
+
+import json
+from pathlib import Path
+from typing import Any
+
+
+def load_state(path: Path) -> dict[str, Any]:
+    if not path.exists():
+        return {}
+    try:
+        data = json.loads(path.read_text(encoding="utf-8"))
+    except json.JSONDecodeError:
+        return {}
+    return data if isinstance(data, dict) else {}
+
+
+def save_state(path: Path, state: dict[str, Any]) -> None:
+    path.parent.mkdir(parents=True, exist_ok=True)
+    path.write_text(json.dumps(state, ensure_ascii=False, indent=2, sort_keys=True), encoding="utf-8")