add prettier config

[beeglebug]

add prettier config

[bhouston]

I had eslint doing cleanup on save in VSCode with all of the auto-formatting. I think you removed this file that enabled that:

https://github.com/bhouston/behave-graph/blob/e596cf818bf034a66b66e9b87c3ca0f46c23eb1f/.vscode/settings.json

Could we just re-enable that? Then this task is done and we do not need prettier.

[bhouston]

Here is your commit where you removed this: 684df3d

[bhouston]

I've added back auto-formatting via es-lint on save here: https://github.com/bhouston/behave-graph/blob/main/.vscode/settings.json

[beeglebug]

The problem with this approach is firstly that vscode settings file is a userland file and not really intended for sharing between developers (and obviously only works for people with vscode).

Secondly eslint is not really a code formatter, it can highlight code issues, but it's slightly out of scope to handle spacing, braces etc. That's where prettier comes in. Ideally we would use both, and let them do their own things.