**Roadmap item:** **What changed:** **Verified:** **Not verified:** - [ ] `cargo fmt --all --check`, `cargo clippy -p --all-targets -- -D warnings`, `cargo test -p `, `cargo xtask layers`, `cargo xtask secrets` - [ ] Docs in this PR: the roadmap line ticked (and new `- [ ]` lines for what's left), STATUS if what works changed, `cargo xtask tools` if tools were added - [ ] No other tool's code, scripts or wording copied (behaviour only; AGENTS.md)