Dockerize React & Go on GCP

I have a small React frontend and a Golang backend that already talk to each other over a REST API. I now need a basic, working Docker setup so I can run both parts on Google Cloud.

Here’s what I’m after:
• One Dockerfile for the React app and another for the Go service.
• A simple docker-compose.yml (or equivalent) that spins them up locally and shows they can communicate on the expected REST endpoints.
• Step-by-step commands to push the two images to Google Container Registry and launch them (Cloud Run or another straightforward GCP option is fine).
• A short README that explains every command, environment variable, and port you use so I can reproduce the process.

I don’t need advanced CI/CD or autoscaling right now—just a clean, minimal containerisation blueprint that works end-to-end.