typescript - evaluate a specific key's type T[K] in a lookup where values are union or of interface

Question

I have a object map of T with value that extends an interface / class or in a similar example members in a union. I would like to lookup the value of a key, K in T and determine the specific subtype or union member, i.e., I don't want the derived type to evaluate to the union or interface. Here an example of an object map with values that extend an interface

class Animal { move() { } }

class Cat extends Animal { meow() { } }

class Dog extends Animal { bark() { } }


const animalLookup: { [K in 'cat' | 'dog']: typeof Animal } = {
  cat: Cat,
  dog: Dog,
}

Now when I lookup a key in animalLookup:

const result = animalLookup['cat'];
// => const result: typeof Animal;

This is expected.

What I've tried is making animalLookup a const with as const. This works as expect, but I loose the ability to make the index type of animalLookup a mapped type, so I can enforce the keys.

Is there a way to make this work so that I can achieve the following while annotating animalLookup with an index signature so I can constrain the keys

const result = animalLookup['cat'];
// => const result: typeof Cat;

EDIT: Added clarification to the question EDIT: updated example to correct values to constructor vs instance types