Export types from the package root

[rattrayalex]

Currently I have to do this:

import type { OpenAPIV3 } from "express-openapi-validator/dist/framework/types";

Looking through the framework/types.ts file, it seems many of the types might be useful to users of the library, though I'm not sure if that's true of all of them.

[cdimascio]

exporting all is unlikely what we want. there is certainly value in separating out the OAS types and exporting them independently

[rattrayalex]

Which types would you like to make public?