Three call sites hardcoded Path("/app/data/cookbook_state.json"), which only
exists in Docker; on a native run the real path is <repo>/data, so the state
file looked missing and cookbook serve-state was silently ignored. Two others
used os.environ.get("DATA_DIR", "data") (a relative fallback, since DATA_DIR is
never set as an env var). Route all five through core.constants.DATA_DIR so the
path is consistent and absolute on both Docker and native.
Part of #3331.
Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>
Kenny Van de Maele
505d8bae5a