Cargo.toml with the release profile and lints, the toolchain pinned to
Rust 1.90.0, a build script that records the git commit for
`cumulus --version`, and rustfmt settings and cargo aliases (`cargo lint`,
`cargo linux`) as in skyshift. DESIGN.md holds the design approved after
the question rounds; README.md has build instructions and the planned keys.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
