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/script/zmtest

@@ -0,0 +1,87 @@
+#!/bin/sh
+
+bindir="$(dirname "$0")"
+
+ZMB="${bindir}/zmb"
+JQ="$(which jq)"
+
+usage () {
+    status="$1"
+    message="$2"
+    [ -n "$message" ] && printf "%s\n" "${message}" >&2
+    echo "Usage: zmtest [OPTIONS] DOMAIN" >&2
+    echo >&2
+    echo "Options:" >&2
+    echo "  -h --help             Show usage (this documentation)." >&2
+    echo "  -s URL --server URL   Zonemaster Backend to query. Default is http://localhost:5000/" >&2
+    echo "  --noipv4              Run the test with IPv4 disabled." >&2
+    echo "  --noipv6              Run the test with IPv6 disabled." >&2
+    echo "                        IPv4 and IPv6 follow the profile setting unless disabled by option." >&2
+    echo "  --lang LANG           A language tag. Default is \"en\"." >&2
+    echo "                        Valid values are determined by backend_config.ini." >&2
+    echo "  --profile PROFILE     The name of a profile. Default is \"default\"." >&2
+    echo "                        Valid values are determined by backend_config.ini except that" >&2
+    echo "                        \"default\" is always a valid value." >&2
+    exit "${status}"
+}
+
+error () {
+    status="$1"
+    message="$2"
+    printf "error: %s\n" "${message}" >&2
+    exit "${status}"
+}
+
+zmb () {
+    server_url="$1"; shift
+    output="$("${ZMB}" --server="${server_url}" "$@" 2>&1)" || error 1 "method $1: ${output}"
+    json="$(printf "%s" "${output}" | "${JQ}" -S . 2>/dev/null)" || error 1 "method $1 did not return valid JSON output: ${output}"
+    error="$(printf "%s" "${json}" | "${JQ}" -e .error 2>/dev/null)" && error 1 "method $1: ${error}"
+    printf "%s" "${json}"
+}
+
+[ -n "${JQ}" ] || error 2 "Dependency not found: jq"
+
+domain=""
+server_url="http://localhost:5000/"
+ipv4=""
+ipv6=""
+lang="en"
+profile="default"
+while [ $# -gt 0 ] ; do
+    case "$1" in
+        -h|--help) usage 2; shift 1;;
+        -s|--server) server_url="$2"; shift 2;;
+        --noipv4) ipv4='--ipv4 false'; shift 1;;
+        --noipv6) ipv6='--ipv6 false'; shift 1;;
+        --lang) lang="$2"; shift 2;;
+        --profile) profile="$2"; shift 2;;
+        *) domain="$1" ; shift 1;;
+    esac
+done
+[ -n "${domain}" ] || usage 2 "No domain specified"
+
+# Start test
+output="$(zmb "${server_url}" start_domain_test --domain "${domain}" ${ipv4} ${ipv6} --profile "${profile}")" || exit $?
+testid="$(printf "%s" "${output}" | "${JQ}" -r .result)" || exit $?
+printf "testid: %s\n" "${testid}" >&2
+
+if echo "${testid}" | grep -qE '[^0-9a-fA-F]' ; then
+    error 1 "start_domain_test did not return a testid: ${testid}"
+fi
+
+# Wait for test to finish
+while true
+do
+    output="$(zmb "${server_url}" test_progress --test-id "${testid}")" || exit $?
+    progress="$(printf "%s" "${output}" | "${JQ}" -r .result)" || exit $?
+    printf "\r${progress}%% done" >&2
+    if [ "${progress}" -eq 100 ] ; then
+        echo >&2
+        break
+    fi
+    sleep 1
+done
+
+# Get test results
+zmb "${server_url}" get_test_results --test-id "${testid}" --lang "${lang}"