fix(sv/nit): align check digit logic with Python reference implementa… - #155

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: osl-incubator/semantic-release-pr-title-check@v1.4.2. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/