feat: add full Zonemaster stack with Docker and Spanish UI

- Clone all 5 Zonemaster component repos (LDNS, Engine, CLI, Backend, GUI)
- Dockerfile.backend: 8-stage multi-stage build LDNS→Engine→CLI→Backend
- Dockerfile.gui: Astro static build served via nginx
- docker-compose.yml: backend (internal) + frontend (port 5353)
- nginx.conf: root redirects to /es/, /api/ proxied to backend
- zonemaster-gui/config.ts: defaultLanguage set to 'es' (Spanish)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

zonemaster-cli/README.md

@@ -0,0 +1,70 @@
+# Zonemaster-CLI
+
+
+## Purpose
+
+This Git repository is one of the components of the Zonemaster software and
+contains the source for the Zonemaster-CLI utility.
+
+For an overview of the Zonemaster software, please see the
+[Zonemaster repository].
+
+
+## Prerequisite
+
+Before you install the Zonemaster-CLI utility, you need the Zonemaster-Engine
+test framework installed. Please see the [Zonemaster Engine installation
+instructions][Zonemaster-Engine installation].
+
+
+## Installation
+
+For installation, see the [installation] document.
+
+
+## Configuration
+
+This repository does not need any specific configuration.
+
+
+## Docker
+
+Zonemaster-CLI is available on [Docker Hub], and can be conveniently downloaded
+and run without any installation. See [USING] Zonemaster-CLI for how to run
+Zonemaster-CLI on Docker.
+
+To build your own Docker image, see the [Docker Image Creation] documentation.
+
+
+## Documentation
+
+Run `zonemaster-cli --help` to get brief descriptions of a selection of the most
+important command line options.
+For complete reference documentation, see the manual page by running `man
+zonemaster-cli`.
+Additional end-user documentation is available in the [USING] document.
+
+When developing Zonemaster-CLI, refer to the [development documentation].
+
+
+## Participation, Contact and Bug reporting
+
+For participation, contact and bug reporting, please see the main
+[Zonemaster README].
+
+
+## License
+
+This is free software under a 2-clause BSD license. The full text of the license can
+be found in the [LICENSE](LICENSE) file included in this respository.
+
+
+[Development documentation]:         https://github.com/zonemaster/zonemaster/blob/master/docs/public/development/cli.md
+[Docker Image Creation]:             https://github.com/zonemaster/zonemaster/blob/master/docs/internal/maintenance/ReleaseProcess-create-docker-image.md
+[Docker Hub]:                        https://hub.docker.com/u/zonemaster
+[Installation]:                      https://github.com/zonemaster/zonemaster/blob/master/docs/public/installation/zonemaster-cli.md
+[USING]:                             https://github.com/zonemaster/zonemaster/blob/master/docs/public/using/cli.md
+[Zonemaster-Engine installation]:    https://github.com/zonemaster/zonemaster/blob/master/docs/public/installation/zonemaster-engine.md
+[Zonemaster README]:                 https://github.com/zonemaster/zonemaster/blob/master/README.md
+[Zonemaster repository]:             https://github.com/zonemaster/zonemaster
+