Node 24 not supported in dev container templates despite being supported in underlying images

Basically the dev container images already support Node v24, but the templates are lagging behind without allowing it as a version.

It should also probably be the default now since it [came out May 2025](https://nodejs.org/en/blog/release/v24.0.0) and has now become the latest LTS version [as-of October 2025](https://nodejs.org/en/blog/release/v24.11.0).

PR #373 should close this. 🙂 