Adds a multi-stage Dockerfile for iios-service (build → pnpm deploy prune →
slim non-root runtime), a docker-entrypoint that runs `prisma migrate deploy`
then starts the server as PID 1, a .dockerignore, a fully-commented
.env.example config contract, and docs/DEPLOYMENT.md (topology, scaling,
release strategy, prod-readiness gaps). Moves prisma to dependencies so the
CLI ships in the prod bundle. Image builds, migrates, and serves /health 200.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
