Extend docs for code contributors

[romainmenke]

With the mono repo we added some complexity and building and testing locally requires a few more steps.

These should be documented.

[Antonio-Laguna]

Let's add a nvmrc here too

[Antonio-Laguna]

Just adding here so we don't forget, python3 requirement.

[romainmenke]

I will document this in the lab function plugin :)

I want to avoid making python3 a real requirement.

[Antonio-Laguna]

Agreed! Just wanted to make sure this wasn't forgotten

[romainmenke]

I totally forgot about that! So reminder was helpful :)