Multi-line recipes run under `bash -c` with no `set -e`, so a mid-recipe failure can be recorded as success

[cailmdaley]

lc executes a recipe as bash -c <recipe> with no set -e (worker.py:56, boundary.py:168-170), so a multi-line command: | block returns the exit status of its last line:

recipe:
  command: |
    python scripts/compute.py --out {output}
    rm -rf $SCRATCH/tmp

If the compute step crashes but the cleanup succeeds, the recipe exits 0. The declared-output existence check catches most such cases, but a file created and then truncated by the crash (e.g. an interrupted np.savez) is committed as a valid artifact with no error anywhere.

This was written by Claude on behalf of Cail.