header_dimensions wrapped Image.open in warnings.catch_warnings with an
error filter for DecompressionBombWarning. catch_warnings is not
thread-safe, so two overlapping captures could leave that error filter
installed for every later Pillow open in the ComfyUI process. Only
Pillow's DecompressionBombError is now mapped to HeaderTooLarge; a size
that only warns is refused by the existing inference pixel cap.