feat: add values.schema.json

[zevisert]

I went through and made a json schema for the values here, since the whole point of using helmet is to reduce boilerplate through standardization. It seems like a good thing to then also have some validation and autocompletions on the available values.

[zevisert]

todo:

• [ ] Need to add some union types for values that accept strings that common.tplvalues.render can render
• [ ] Need to decide where to host these values
• [ ] Need to remove required fields, since values.yaml can be composed

[zevisert]

Sorry, didn't mean to close this - I didn't realize I named the branch patch-1 (originally did this on github.dev) and I was cleaning up my branches.