During the work for HAC-491 there was some internal API and external API declared in the `lib-core` index file. These need to be reconciled as to not expose internal API out of the NPM Package.

Acceptance Criteria

• Split the index file in two
  • index.ts, should cover the exposed api
  • sdk-index.ts (example name, use whatever makes sense) should be for other packages to import from the lib-core to get a hold of types – anything common should end up in the `common` package