feat(deploy): production Dockerfiles, compose stack, and runbook

- Multi-stage Dockerfiles for web/api/generator (pnpm workspace install,
  tsx runtime — workspace packages are raw TS, same model as runner-template).
- docker-compose.prod.yml: postgres + redis + the three app services.
  api/generator/web use host networking so the generator's host-port probe
  is correct and every service shares one address space; api + generator
  mount the Docker socket. Binds nothing on 80/443 — safe beside other apps.
- Optional Traefik reverse proxy in infra/traefik/ (heavily gated — only if
  the box has no existing proxy).
- .env.production.example, .dockerignore, DEPLOY.md (Cloudflare zone, GoDaddy
  nameserver switch, server deploy, Google Cloud Console OAuth app).
- api/generator `start` now runs via tsx; `node dist/index.js` could never
  resolve the raw-TS workspace imports.

All three images verified building clean; the API container boots under tsx.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

infra/traefik/.env.example

@@ -0,0 +1,3 @@
+# Copy to infra/traefik/.env — used only by docker-compose.traefik.yml.
+# Email Let's Encrypt uses for expiry notices.
+ACME_EMAIL=marco.frangiskatos@gmail.com