Update code to work with `erasableSyntaxOnly`

[jakeleventhal]

TypeScript 5.8 released a new feature for erasableSyntaxOnly. The output of generated schemas should not use enums.

[JoviDeCroock]

This might be an issue for GraphQL Code generator? https://github.com/dotansimha/graphql-code-generator - there's probably a config option to disable enums but this isn't the right repository