Stack improvements

[dwightjack]

@victorgarciaesgi here are some updates related to the project.

In the latest commits I had to update some configuration to make both the doc and build jobs work.

Basically the latest versions of microbundle, vite and vuepress had a number of conflicts (related to the version of postcss) that prevented them to work together. Also the latest npm@8 had some issues on CI that forced me to add the legacy-peer-deps command in the .nvmrc file.

To summarize the changes

• CI
  • update actions versions
  • use .nvmrc to set the node version on ci
  • use actions/setup-node built-in cache functionality instead of action/cache
• stack
  • remove .node-version file because it was redundant
  • update node version to the latest LTS
  • mode vuepress related stuff in docs/package.json (we now have a nested node_modules and lock file)

I would like to explore some new tools for the stack in the future and I'd like to know your opinion:

• microbundle --> unbuild: less dependencies (microbundle support, for example, postcss but we don't use it), but maybe larger bundle?
• vuepress --> vitepress: we already use vite for vitest and the examples folder. I am not sure about the migration path, because it's still in alpha 😅