The binopt cache from b4cb10b saved only binaryen-hoist-build/bin, but the
tools dynamically link lib/libbinaryen.so, so the first cache HIT (run
28585074335) failed all 7 tools' finalize with a loader error. Cache bin/ +
lib/, bump the key to binopt-v2 (Ubicloud never re-saves an exact-key hit, so
the poisoned v1 entry can't be repaired in place), and make the
BINARYEN_TRUST_PREBUILT guard exec both tools with --version instead of -x
existence checks so an incomplete restore falls through to a source build.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NTxTrY9on6A8gLvogFbGiy
e01256b54d