- spec: add one-line cross-link to HOTFIXES entry per CLAUDE.md Spec-contract policy - HOTFIXES: rename heading from "fb-32" to "p9-fb-32" matching the rest of the file's full-ID convention - config: defensive assert before string-replace in negative TOML test guards against default-value drift causing unhelpful unwrap Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>