Improve inference on parametrized record fields

[schicks]

When a Field is constructed from a parametrized type, it can't correctly infer the underlying type without an explicit annotation. This is trivial to add, but irritating boilerplate.

const person = Record("person", {
    name: Field(String()),
    age: Field(Long()),
  });
const field = Field(person) // infers RequiredField<unknown>
const betterField = Field<typeof person>(person) //infers RequiredField<{name: string, age: number}>

Ideally fields would automatically do this inference, rather than needing to be "prompted" in this way. This feels like a higher kinded types problem though, so I'm not sure if there is a solution.

The issue exists for any field constructed with an underlying type which has a parameter.