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-backend/Makefile.PL

@@ -0,0 +1,97 @@
+use inc::Module::Install;
+use Module::Install::Share;
+
+name 'Zonemaster-Backend';
+all_from 'lib/Zonemaster/Backend.pm';
+repository 'https://github.com/zonemaster/zonemaster-backend';
+bugtracker 'https://github.com/zonemaster/zonemaster-backend/issues';
+
+# "2.1.0" could be declared as "2.001" but not as "2.1"
+# (see Zonemaster::LDNS below)
+
+requires
+  'Class::Method::Modifiers'        => 1.09,
+  'Config::IniFiles'                => 0,
+  'DBI'                             => 1.635,
+  'Daemon::Control'                 => 0.001007,
+  'File::ShareDir'                  => 0,
+  'File::Slurp'                     => 0,
+  'HTML::Entities'                  => 0,
+  'JSON::PP'                        => 0,
+  'JSON::RPC'                       => 1.01,
+  'JSON::Validator'                 => 4.00,
+  'Locale::TextDomain'              => 1.20,
+  'Log::Any'                        => 0,
+  'Log::Any::Adapter::Dispatch'     => 0,
+  'Log::Dispatch'                   => 0,
+  'LWP::UserAgent'                  => 0,
+  'Mojolicious'                     => 7.28,
+  'Moose'                           => 2.04,
+  'Net::IP::XS'                     => 0,
+  'Parallel::ForkManager'           => 1.12,
+  'Plack::Builder'                  => 0,
+  'Plack::Middleware::ReverseProxy' => 0,
+  'Role::Tiny'                      => 1.001003,
+  'Router::Simple::Declare'         => 0,
+  'Starman'                         => 0,
+  'Try::Tiny'                       => 0.12,
+  'Zonemaster::LDNS'                => 5.000001,  # v5.0.1
+  'Zonemaster::Engine'              => 8.001000,  # v8.1.0
+  ;
+
+test_requires 'DBD::SQLite' => 1.66;
+test_requires 'Test::Differences';
+test_requires 'Test::Exception';
+test_requires 'Time::Local' => 1.26;
+test_requires 'Test::NoWarnings' => 0;
+
+recommends 'DBD::mysql';
+recommends 'DBD::Pg';
+recommends 'DBD::SQLite' => 1.66;
+
+install_share;
+
+install_script 'zonemaster_backend_rpcapi.psgi';
+install_script 'zonemaster_backend_testagent';
+install_script 'zmtest';
+install_script 'zmb';
+
+no_index directory => 'CodeSnippets';
+no_index directory => 'Doc';
+
+# Make all platforms include inc/Module/Install/External.pm
+requires_external_bin 'find';
+if ($^O eq "freebsd") {
+    requires_external_bin 'gmake';
+};
+
+sub MY::postamble {
+    my $text;
+    if ($^O eq "freebsd") {
+        # Make FreeBSD use gmake for share/Makefile
+        $text = 'GMAKE ?= "gmake"' . "\n"
+            . 'pure_all :: share/Makefile' . "\n"
+            . "\t" . 'cd share && $(GMAKE) all' . "\n";
+    } else {
+        $text = 'pure_all :: share/Makefile' . "\n"
+            . "\t" . 'cd share && $(MAKE) all' . "\n";
+    };
+    my $docker = <<'END_DOCKER';
+
+docker-build:
+	docker build --tag zonemaster/backend:local --build-arg version=$(VERSION) .
+
+docker-tag-version:
+	docker tag zonemaster/backend:local zonemaster/backend:$(VERSION)
+
+docker-tag-latest:
+	docker tag zonemaster/backend:local zonemaster/backend:latest
+
+END_DOCKER
+
+    return $text . $docker;
+};
+
+install_share;
+
+WriteAll;