Create plugin: Set scaffold nvmrc to Node 24

[alebgl77]

What this PR does / why we need it:

Updates the shared create-plugin .nvmrc template from Node 22 to Node 24 so newly generated plugins select Node 24.

The change is intentionally limited to the scaffold runtime selector. It does not change the supported engine range or workflow versions.

Which issue(s) this PR fixes:

Fixes #2827

Special notes for your reviewer:

Not run locally because Git access was unavailable in the execution environment. The change is limited to one static template file; repository CI will validate the package and scaffold matrix.

[cla-assistant]

All committers have signed the CLA.

[cla-assistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}