Generate a values.schema.json for Workbench, Connect, and Package Manger to improve values.yaml authoring experience

[SamEdwardes]

Authoring the values.yaml is error prone because there are many keys, and the nesting is deep. It would help users if their IDE provided linting and auto-completion. This can be achieved with a values.schema.json. For example:

# yaml-language-server: $schema=./values.schema.json
replicas: 1

fullnameOverride: posit-connect

sharedStorage:
  create: true
  name: posit-connect-pvc
  mount: true

I see that Chronicle already has values.schema.json, so maybe the same process can be implemented for Workbench, Connect, and Package Manager.

[SamEdwardes]

Example of creating one for Connect:

helm plugin install https://github.com/losisin/helm-values-schema-json.git --verify=false

cd apps/posit-connect \
    && helm show values rstudio/rstudio-connect > default-values.yaml \
    && helm schema \
      --values default-values.yaml \
      --output values.schema.json \
      --use-helm-docs \
      --no-additional-properties \
      --schema-root.title "Posit Connect values.yaml Schema"