test(infra): poll-for-event race fixes + watchdog timeout bump + spec update

tests/test_z_negative_flows.py

@@ -112,10 +112,13 @@ def test_mock_timeout(live_gui) -> None:
   client.set_value("ai_input", "Trigger timeout")
   client.click("btn_gen_send")
 
-  # Wait for terminal response
+  # Wait for terminal response. The mock subprocess sleeps for 65s
+  # then exits; allow 180s for the event to land (the io_pool is busy
+  # in batched live_gui context, and the event propagation through
+  # _pending_gui_tasks can be slow under contention).
   event = None
   start = time.time()
-  while time.time() - start < 80:
+  while time.time() - start < 180:
    ev = client.wait_for_event("response", timeout=5)
    if ev and ev.get("payload", {}).get("status") != "streaming...":
     event = ev