Allow production builds for UI packages

[caponetto]

What changes were proposed in this pull request?

Targets in the Makefile that touch the UI building process now have prod and dev versions. The UI packages offer both dev and prod scripts but currently, we are using only the dev version, which is useful only for development, not for the production environment. The dev version is larger since source maps and unoptimized files for the UI packages are included. Now, the prod version does not include source maps, and the source is optimized for production.

❯ make help
build-ui-dev                   Build UI packages for development
build-ui-prod                  Build UI packages for production
clean                          Make a clean source tree and uninstall extensions
container-images               Build all container images
docs                           Build docs
elyra-image-env                Creates a conda env consisting of the dependencies used in images
install-all-dev                Build and install for development, including examples
install-all-prod               Build and install for production, including examples
install-dev                    Build and install for development
install-examples               Install example pipeline components
install-prod                   Build and install for production
install-server                 Build and install backend
lint                           Run linters
package-ui-dev                 Package UI for development
package-ui-prod                Package UI for production
publish-container-images       Publish all container images
release                        Build wheel file for release
test                           Run all tests (backend, frontend and cypress integration tests)
watch                          Watch packages. For use alongside jupyter lab --watch

Cherry-picked from ODH Elyra:

• Allow production builds for UI packages opendatahub-io/elyra#50
• Add missing make target to dev builds opendatahub-io/elyra#91

How was this pull request tested?

Build Elyra with both make clean install-all-dev and make clean install-all-prod, and check the resulting whl file size and contents.

Also the CI on my fork: https://github.com/caponetto/opendatahub-io-elyra/actions/runs/12582298698

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[caponetto]

cc @lresende (as I'm not able to assign reviewers)