Showcase how to build Web Components using Angular Elements, and 
use multiple pre-build Angular Web Components in Angular Shell App.
# build script used by `ngx-build-plus` via `configHook` in `angular.json` (one time only)
npm run tsc -- -p tools/tsconfig.tools.json
# build micro-apps before building webapp
ng build chat-app --prod
# build shell webapp
ng build webapp --prodrun sever with prod build
npm run server