Stabilize task execution and UI lifecycle

tests/unit/test_llm_pause.py

@@ -0,0 +1,37 @@
+from artemis.services import llm
+
+
+class _RecordingEngine:
+    current_step_id = "step-7"
+
+    def __init__(self):
+        self.trace_kwargs = None
+        self.published = None
+
+    def record_trace(self, **kwargs):
+        self.trace_kwargs = kwargs
+
+    def _publish(self, event_type, payload):
+        self.published = (event_type, payload)
+
+
+def test_pause_error_is_persisted_and_published(monkeypatch, tmp_path):
+    engine = _RecordingEngine()
+    monkeypatch.setattr(llm, "_CURRENT_DATA_ENGINE", engine)
+    monkeypatch.setattr(llm.settings, "TRACES_PATH", str(tmp_path / "traces"))
+
+    pause_file = llm._handle_llm_pause_and_resume(RuntimeError("503 high demand"))
+
+    assert pause_file.read_text() == "LLM Error: 503 high demand"
+    assert engine.trace_kwargs == {
+        "type": "llm_call",
+        "name": "llm_pause",
+        "payload": {"error": "503 high demand", "pause": True},
+        "step_id": "step-7",
+        "status": "failed",
+    }
+    event_type, payload = engine.published
+    assert event_type == "task_paused"
+    assert payload["error"] == "503 high demand"
+    assert payload["step_id"] == "step-7"
+    assert isinstance(payload["timestamp"], float)