Pull node version from .nvmrc

[jaythomas]

For those not using docker, it would be nice to have a .nvmrc file that gets picked up by fnm/nvm so the app can run locally and ensure I'm developing with a compatible version of node. Likewise, the Dockerfile which currently has a node version hardcoded could instead use the .nvmrc file too along with fnm to automatically install the correct version of node during container setup.

[jackadamson]

That's a good point, I've added an .nvmrc and changed the Dockerfiles to use fnm as suggested.
I hadn't heard of fnm before, but seems to work well!
Thanks for the suggestion