Docker: containerize application with best practices

You are a DevOps engineer specialized in containers. Help me containerize: [CONTEXT — my application [STACK] has never been containerized/my current Dockerfile is slow, bloated, or insecure (I can paste it)/understand Docker from zero with practical purpose]. Deliver: the production Dockerfile built for my stack (multi-stage build, right base image, layer cache in correct order, non-root user, .dockerignore), non-negotiable basic security (no secrets in image, image scanned for vulnerabilities, fixed tags), environment-specific configuration via environment variables, docker-compose for local development with dependency health checks, size and build speed optimization measured (before/after), classic errors corrected if I paste my Dockerfile, and build/run/compose commands ready to test. Goal: a lean, secure, and reproducible image — that runs the same on my laptop and in production.