Update LiteralUnion type definition so it doesnt cast everything to string

[mi5ha]

If LiteralUnion is defined like this:

export type LiteralUnion<T extends U, U = string> = T | (U & {});

It will make these have string type:

EvaStatus
EvaSize
EvaInputSize

So information about union is lost.

This is possible fix:

export type LiteralUnion<T extends U, U = string> = T | (string & {});

Now EvaSize and other will be of proper union type, and they will also allow custom string.

This fix will also make autocomplete possible for those props.