SDK 0.2.1 release

Highlights

• Rust SDK footprint trimmed for consumer binaries: leaner tokio/futures/reqwest feature sets, and TLS is now a Cargo feature (default rustls-tls, or native-tls for a much smaller binary).
• Rust SDK upgraded to reqwest 0.13.
• Dependency and security updates across all SDKs.
• Documentation polish: Everruns logo in the README, plainer punctuation in prose.

In the changelog

• Everruns Rust SDK can use native TLS for smaller binaries

See the GitHub release and the full release notes for every pull request in this version.