fix(mma): Replace token stats stub with real comms log extraction in run_worker_lifecycle

Task 2.1 of mma_pipeline_fix_20260301: capture comms baseline before send(), then sum input_tokens/output_tokens from IN/response entries to populate engine.tier_usage['Tier 3'].

tests/test_conductor_engine.py

@@ -293,3 +293,31 @@ def test_run_worker_lifecycle_pushes_response_via_queue(monkeypatch: pytest.Monk
   assert call_args[3]["status"] == "done"
  assert ticket.status == "completed"
 
+def test_run_worker_lifecycle_token_usage_from_comms_log(monkeypatch: pytest.MonkeyPatch) -> None:
+ """
+    Test that run_worker_lifecycle reads token usage from the comms log and
+    updates engine.tier_usage['Tier 3'] with real input/output token counts.
+    """
+ ticket = Ticket(id="T1", description="Task 1", status="todo", assigned_to="worker1")
+ context = WorkerContext(ticket_id="T1", model_name="test-model", messages=[])
+ fake_comms = [
+  {"direction": "OUT", "kind": "request", "payload": {"message": "hello"}},
+  {"direction": "IN", "kind": "response", "payload": {"usage": {"input_tokens": 120, "output_tokens": 45}}},
+ ]
+ monkeypatch.setattr(ai_client, 'send', MagicMock(return_value="Done."))
+ monkeypatch.setattr(ai_client, 'reset_session', MagicMock())
+ monkeypatch.setattr(ai_client, 'get_comms_log', MagicMock(side_effect=[
+  [],         # baseline call (before send)
+  fake_comms, # after-send call
+ ]))
+ from multi_agent_conductor import run_worker_lifecycle, ConductorEngine
+ from models import Track
+ track = Track(id="test_track", description="Test")
+ engine = ConductorEngine(track=track, auto_queue=True)
+ with patch("multi_agent_conductor.confirm_spawn") as mock_spawn, \
+ patch("multi_agent_conductor._queue_put"):
+  mock_spawn.return_value = (True, "prompt", "ctx")
+  run_worker_lifecycle(ticket, context, event_queue=MagicMock(), loop=MagicMock(), engine=engine)
+ assert engine.tier_usage["Tier 3"]["input"] == 120
+ assert engine.tier_usage["Tier 3"]["output"] == 45
+