- Add DOCKER_HOST export to Makefile for remote Docker daemon
- Create multi-stage Dockerfile:
- Build stage: golang:1.24-alpine with gcc, make, git
- Runtime stage: alpine with ca-certificates, gnupg
- Runs as non-root 'secret' user
- Add Makefile targets:
- docker: build container as sneak/secret
- docker-run: run container interactively
- Add .dockerignore to exclude build artifacts but keep .git
for potential linker flags
Container includes GPG support for PGP unlockers and runs on Linux,
making it suitable for cross-platform testing and deployment.