ci: add GitHub Actions workflow for build, lint and test

[chaosreload]

Summary

Add a CI workflow that runs on every push and pull request to .

Checks

• cargo fmt --check — enforce consistent formatting
• cargo clippy — lint for common Rust mistakes
• cargo build — verify debug build
• cargo build --release — verify release build
• cargo test — run unit tests

Notes

• Uses to cache cargo registry and build artifacts for faster runs
• clippy runs without for now to avoid blocking PRs with pre-existing warnings; can be tightened in a follow-up
• Targets to match the recommended deployment environment