Update GitHub Actions to Node 24 releases

[fruwe]

Summary

• pin every official GitHub Action in CI and release workflows to the requested immutable Node 24-based release commit
• preserve the configured Python and Node toolchain versions and all publishing behavior
• correct the obsolete release comment about the existing npm trusted-publishing job

Validation

• workflow YAML parsing
• Python: Ruff and 12 tests
• Rust: release build, Clippy with warnings denied, and 8 tests
• Node: dispatcher tests
• no actions/*@v4 or actions/*@v5 references remain
• package version files unchanged
• git diff --check

Fixes #4