feat(operator): production build + k3s deployment

- Dockerfile for the operator app (same pattern as portal/booking).
- Env-driven auth/app base URLs in nuxt.config so one build serves
  dev (.local) and production (.eu).
- Deployment + Service + Ingress on operator.dezky.eu.
- Add operator to the typecheck matrix.

.github/workflows/ci.yml

@@ -19,6 +19,7 @@ jobs:
           - { name: portal, dir: apps/portal }
           - { name: booking, dir: apps/booking }
           - { name: website, dir: apps/website }
+          - { name: operator, dir: apps/operator }
     defaults:
       run:
         working-directory: ${{ matrix.target.dir }}