[bug] package subpath error

[marionnegp]

Description of the issue

When running npm run serve in the red-hat-design-system repo, terminal shows this error:

node:internal/process/esm_loader:40
      internalBinding('errors').triggerUncaughtException(
                                ^
Error [ERR_PACKAGE_PATH_NOT_EXPORTED]: Package subpath './custom-elements-manifest/lib/Manifest.js' is not defined by "exports" in /Users/mapatel/Sites/red-hat-design-system/node_modules/@patternfly/pfe-tools/package.json imported from /Users/mapatel/Sites/red-hat-design-system/scripts/playgrounds.ts
    at exportsNotFound (node:internal/modules/esm/resolve:294:10)
    at packageExportsResolve (node:internal/modules/esm/resolve:641:9)
    at packageResolve (node:internal/modules/esm/resolve:827:14)
    at moduleResolve (node:internal/modules/esm/resolve:901:20)
    at defaultResolve (node:internal/modules/esm/resolve:1121:11)
    at nextResolve (node:internal/modules/esm/hooks:865:28)
    at resolve (file:///Users/mapatel/Sites/red-hat-design-system/node_modules/tsx/dist/esm/index.mjs?1723134362329:2:3893)
    at async nextResolve (node:internal/modules/esm/hooks:865:22)
    at async Hooks.resolve (node:internal/modules/esm/hooks:303:24)
    at async handleMessage (node:internal/modules/esm/worker:196:18) {
  code: 'ERR_PACKAGE_PATH_NOT_EXPORTED'
}

Node.js v20.10.0
❌ [playgrounds] Failed with exit status 1

Steps to reproduce

I'm seeing this error specifically from the feat/rh-icon branch in the red-hat-design-system repo.

1. Open the feat/rh-icon branch
2. If ./custom-elements-manifest/lib/Manifest.js is not in node_modules > @patternfly > pfe-tools > package.json file, run npm run serve

Expected behavior

Terminal should say something like Server at http://localhost:8080/ and allow me to view a preview of ux.redhat.com

[bennypowers]

I'd like to resolve this by exporting constructor functions (like getAllProjectManifests) from a pfe-tools custom elements manifest entrypoint module