Web demo fails if generation is stopped before completion

Hi, If in the web demo the stop button is pressed mid-generation, the app terminates. ``` *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'NSWindow should only be instantiated on the main thread!' ... Traceback (most recent call last): File "<frozen runpy>", line 198, in _run_module_as_main File "<frozen runpy>", line 88, in _run_code File "/Users/levinho/env1/lib/python3.12/site-packages/torch/distributed/run.py", line 923, in <module> main() File "/Users/levinho/env1/lib/python3.12/site-packages/torch/distributed/elastic/multiprocessing/errors/__init__.py", line 355, in wrapper return f(*args, **kwargs) ^^^^^^^^^^^^^^^^^^ File "/Users/levinho/env1/lib/python3.12/site-packages/torch/distributed/run.py", line 919, in main run(args) File "/Users/levinho/env1/lib/python3.12/site-packages/torch/distributed/run.py", line 910, in run elastic_launch( File "/Users/levinho/env1/lib/python3.12/site-packages/torch/distributed/launcher/api.py", line 138, in __call__ return launch_agent(self._config, self._entrypoint, list(args)) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/Users/levinho/env1/lib/python3.12/site-packages/torch/distributed/launcher/api.py", line 269, in launch_agent raise ChildFailedError( torch.distributed.elastic.multiprocessing.errors.ChildFailedError: ============================================================ ml_mdm/clis/generate_sample.py FAILED ``` I can look into this error and will post updates to this thread.