refactor: nominal typing

[seaerchin]

note: this is marked as draft to ensure that the design is sound before fixing up the tests/methods in the controller layer

Problem

Currently, our types for email and mobile phone number are string - this results in possibly incorrect definitions where we want to use a Email type but we pass in a normal string, which is not caught by the type system.

a more detailed discussion can be found here!

Solution

1. use ts-brand to get pseudo nominal typing through the use of a brand.
2. create a companion object with the same name as the type so that conversion to/from the type is painless

Design Considerations

1. zod was not used due to its limitations - z.infer associates input types with output types of the schema. Hence, even though we validate it, the output is still string, which doesn't help.

[karrui]

i think you are overcomplicating this. why can't we just use type-fest's Opaque type instead of a relatively unused and not-updated library?

to create an opaque type, we just need a creator method, e.g.

import { Opaque } from 'type-fest'
type Email = Opaque<string, 'Email'>
const createEmail = (email: string): Email => {
  // Can even add validation here and throw error or something
  return email as Email;
}

you really don't need something so complex like assert, etc.

everything else should stick to the same doesn't it? Only functions that absolutely need the correct type to declare it

[seaerchin]

the reason why we can't use the Opaque type is because it's meant as a black box - once we use it, there's no way for us to extract the type out from Opaque because it's set as Type & {readonly __opaque__: Token} where there isn't a witness to the base type.

wrt assert and extract i just wanted to add utility methods for ppl to use AHAH so that the api is sensible and easy to use

[karrui]

we should not need to extract the type out. any arguments of 'string' (for example) will be able to be used with Opaque<string, 'Key> since the Opaque type is a superset.

[karrui]

should this also be of Email[] type