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/configuration/profiles.md

@@ -0,0 +1,30 @@
+# Profiles
+
+## Default profile
+
+The default profile is documented in the [profile properties] section
+of the Zonemaster::Engine::Profile module.
+
+The default profile can be extracted from Zonemaster-Engine to a file using this command.
+
+```sh
+perl -MZonemaster::Engine::Test -E 'say Zonemaster::Engine::Profile->default->to_json' | jq -S . > profile.json
+```
+
+## Creating profiles
+
+Some properties are empty by default such as `logfilter` and
+`test_cases_vars`. Those properties are not present in the default
+profile. For an example of their usage, refer to the additional file,
+[profile_additional_properties.json].
+
+The content of the two files, as-is or modified, can be merged into a custom
+profile file that can be loaded by Zonemaster-Engine. Both Zonemaster-CLI and
+Zonemaster-Backend have direct options for loading a custom profile file.
+
+A custom profile file only has to contain those [properties][profile properties]
+that it should override.
+
+
+[profile_additional_properties.json]:  https://github.com/zonemaster/zonemaster-engine/blob/master/share/profile_additional_properties.json
+[Profile properties]:                  https://metacpan.org/pod/Zonemaster::Engine::Profile#PROFILE-PROPERTIES