Implement Pick[T, K] and Omit[T, K] type utilities

[AliiiBenn]

Description

Add Pick and Omit type utilities similar to TypeScript's Pick and Omit.

Specification

Pick[T, K] - Select only the specified properties K from type T
Omit[T, K] - Exclude the specified properties K from type T

class User:
    name: str
    email: str
    age: int

Pick[User, 'name' | 'email'] = { name: str; email: str }
Omit[User, 'age'] = { name: str; email: str }

Implementation notes

• K should be a union of literal keys
• Should work with classes and TypedDict
• Can leverage existing Attrs and GetMemberType

References

• TypeScript Pick: https://www.typescriptlang.org/docs/handbook/utility-types.html#picktype-keys
• TypeScript Omit: https://www.typescriptlang.org/docs/handbook/utility-types.html#omittype-keys

Acceptance criteria

• Pick works with classes
• Omit works with classes
• Pick works with TypedDict
• Omit works with TypedDict
• Runtime evaluator implemented
• Unit tests added