- create_app reads distributed_executor_backend with getattr(..., None): the MLX
server passes a SimpleNamespace without it, so since #1746 the server could not
start (28 test_openai_video_client failures). An explicit external_launcher
request is still rejected.
- test_cpu_sdpa patches fastvideo.platforms._current_platform instead of
current_platform. monkeypatch restored the real platform as a module attribute
that shadowed the lazy __getattr__, so later tests that fake _current_platform
(gpu_worker dist timeout, ROCm detection, selector role override) failed on
GPU hosts.
GB200 unit lane, A/B on one tray: main 36 failures, this change 0 (2720 passed).