CodeBench: Rust-tuki (--lang rust), golden example todo-rs, Dockerfile.cargo-test

- golden-examples/todo-rs/: Axum 0.8 + SQLx + SQLite, 10 testiä
- prompts/code-rs.md: Rust-koodingenerointiprompt
- Dockerfile.cargo-test: rust:1.87-slim testikontti
- benchmark.mjs: --lang python|rust, kieliriippuvainen golden example,
  parseri tukee cargo test -tuloksia, src/ alihakemistot

kipina-codebench/Dockerfile.cargo-test

@@ -0,0 +1,4 @@
+FROM rust:1.87-slim
+RUN apt-get update && apt-get install -y pkg-config libssl-dev && rm -rf /var/lib/apt/lists/*
+WORKDIR /work
+ENTRYPOINT ["sh", "-c", "cp -r /src/* . && cargo test 2>&1"]