82 feature request suggestion create fe image workflow

[lmcdonough]

This pull request introduces a new GitHub Actions workflow for building and pushing the frontend Docker image, and also updates the Dockerfile to improve the build process and runtime configuration. The key changes are grouped by theme below:

GitHub Actions Workflow:

• Added a new workflow .github/workflows/build_and_push_image.yml to build and push the frontend Docker image on specific events (push, pull request, workflow dispatch). This includes setting up QEMU for multi-arch builds, logging into GitHub Container Registry, building and pushing the Docker image, and signing the image with Cosign.

Dockerfile Enhancements:

• Updated Dockerfile to include build platform context, optional diagnostics, and improved handling of build-time arguments. This ensures better multi-arch support and more informative build logs.
• Simplified environment variable handling by consolidating echo statements into a single RUN command for better readability and debugging.
• Changed the exposed port from a dynamic environment variable to a fixed port 3000 to align with the frontend service configuration.

Changes

• Modifies Dockerfile
• Creates GitHub Actions Workflow to build images and store in ghcr

Note pairs with backend Issue #82

[jhodapp]

Looking very clean and great Levi, thank you for this. I have a few suggested changes inline, nothing too major and then I'm happy to approve.

Also, is there an easy way for me to test this ahead of landing it since it's isolated to just your branch for this PR for now?

[jhodapp]

Looks great, thank you!