fix(transaction): keep a server INVITE's final response after the ACK ends it - #174

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/checkout@v4. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/

unused optional dependency `rustls-pki-types`