Stream AWS fallback logs while commands run (#8783)
The torch-latest AWS fallback currently shows prepare and test output
only after each SSM Run Command finishes. Long dependency setup and test
runs can therefore appear silent in GitHub Actions even while they are
making progress,
which delays diagnosis and makes a healthy run difficult to distinguish
from a stalled one.
Enable native SSM CloudWatch output for fallback commands and poll the
known stdout and stderr streams alongside the existing command-status
poll. The controller advances each stream with its forward token, sends
every new line through the existing public-output sanitizer, flushes it
promptly, and drains available events at terminal status without
replaying the inline response.
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Signed-off-by: Masahiro Tanaka <tanaka.masahiro@gmail.com>
