Document Services - Intro, how to generate, what are they, how they relate to GraphQL/SDL

[dthyresson]

See: https://redwoodjs.com/docs/services

Most of the Services documentation noted above concerns "Secure Services" and the before resolver -- whose implementation is being depreciated in 0.37 in favor of auth validation directives.

But, there is little documentation about what services actually are and what they do.

Suggestions:

• intro/overview
• how to generate
• what are they used for (Prisma and other datas fetching/manipulation)
• how they relate to GraphQL and SDL
• what are those extra relation functions created in my service?
• when to use a service and when to use a shared function in lib
• calling a service from a serverless function
• securing when used in GraphQL

[dthyresson]

@jtoar and @cannikin do the current round of docs close this item out?

[cannikin]

It's probably 80% of the way there..may want to update the bullet list in the first comment, as the only things left are:

• how to generate
• when to use a service and when to use a shared function in lib
• what arguments are sent in when called via GraphQL