A self-review of the device-output canvas found the rare near-black
branch calling the numpy _background_max_outside with a device tensor -
it happened to work through the numpy/torch API overlap, but it made an
undocumented per-frame device read inside the branch and would break on
a torch-only API change. The branch is rare by construction, so this one
frame is downloaded explicitly, exactly like the full-canvas fallback
next to it.
Also adds the device-output pin of the near-black branch itself
(test_the_device_canvas_keeps_the_near_black_full_canvas_fallback): the
rare path now runs in the canvas mode in the gate instead of only in
production.
WildAi
c7e0674086