POST /gc/place stamps the body gc.place and forwards it; the plugin keeps the
key and the crate is kept when the run ends, so nothing is kept here. Spec:
docs rust-link/PROTOCOL.md §20.9.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01E14m6SuuY6i1vASFeGDBeY