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/docs/public/specifications/test-zones/MethodsV2/README.md

@@ -0,0 +1,29 @@
+# Specification of test scenarios for MethodsV2
+
+This document structure contains test scenario specifications for [MethodsV2],
+which is not a Test Case module. Instead it is a collection of Method
+specifications referred to by the Test Case specifications and implemented by
+Perl methods used in the implementations of the Test Cases.
+
+The purpose of the test scenarios for [MethodsV2] is to verify that the
+implementation of the methods matches the specifications.
+
+Test scenarios specification for the following methods are available:
+
+* [Get parent NS IP addresses]
+* [Get delegation NS names and IP addresses]
+* [Get zone NS names and IP addresses]
+
+Test scenarios specification:
+
+* [Specification of test scenarios for MethodsV2](methodsv2.md)
+
+Test scenarios for [Test Case] implementations and test scenarios for Perl
+modules in Zonemaster-Engine are not in this structure. Instead they can
+be found in sibling structures.
+
+[Get delegation NS names and IP addresses]:        ../../tests/MethodsV2.md#method-get-delegation-ns-names-and-ip-addresses
+[Get parent NS IP addresses]:                      ../../tests/MethodsV2.md#method-get-parent-ns-ip-addresses
+[Get zone NS names and IP addresses]:              ../../tests/MethodsV2.md#method-get-zone-ns-names-and-ip-addresses
+[MethodsV2]:                                       ../../tests/MethodsV2.md 
+[Test Case]:                                       ../../tests/README.md