v0.2.7

Security and dependency updates

• Upgrade zstd to 0.14.3 and HPKE dependencies to patched versions, resolving the RustSec findings and yanked dependency in the previous lockfiles.
• Both workspace lockfiles pass cargo audit --deny yanked.

See the v0.2.7 changelog for the full change list.

Full Changelog: v0.2.6...v0.2.7