CLI: a closed stdout pipe exits 141 silently (was E_INTERNAL); example avoids head under pipefail

Found by the P10 fresh-VM run: `simurg inspect … | head` raised BrokenPipeError, reported as
an internal error, and stopped examples/gsa_demo.sh (set -o pipefail). run_guarded now flushes
stdout inside the guard and maps BrokenPipeError to ExitCode.SIGPIPE (141) without a message.
p10.sh: SKIP_DOCKER/SKIP_CONDA, clearer digest report; p10t.sh runs build+pip+tutorial only.

scripts/cloud/tasks/p10t.sh

@@ -0,0 +1,3 @@
+#!/bin/bash
+# P10 acceptance without the Docker and conda parts (already verified): build, pip installs, tutorial, digests.
+SKIP_DOCKER=1 SKIP_CONDA=1 bash "$(dirname "$0")/p10.sh" "$@"