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/test-zone-data/Nameserver-TP/nameserver15/nameserver15.xa

@@ -0,0 +1,80 @@
+$ORIGIN nameserver15.xa.
+$TTL 3600
+
+@       SOA     ns1 admin. (
+                2022112300      ; serial
+                6h              ; refresh
+                1h              ; retry
+                1w              ; expire
+                1d )            ; minimum
+
+        NS    ns1
+        NS    ns2
+
+ns1     A     127.17.15.21
+ns1     AAAA  fda1:b2:c3:0:127:17:15:21
+ns2     A     127.17.15.22
+ns2     AAAA  fda1:b2:c3:0:127:17:15:22
+
+$ORIGIN no-version-revealed-1.nameserver15.xa.
+@       NS      ns1
+ns1     A     127.17.15.31
+ns1     AAAA  fda1:b2:c3:0:127:17:15:31
+
+$ORIGIN no-version-revealed-2.nameserver15.xa.
+@       NS      ns1
+ns1     A     127.17.15.32
+ns1     AAAA  fda1:b2:c3:0:127:17:15:32
+
+$ORIGIN no-version-revealed-3.nameserver15.xa.
+@       NS      ns1
+ns1     A     127.17.15.33
+ns1     AAAA  fda1:b2:c3:0:127:17:15:33
+
+$ORIGIN no-version-revealed-4.nameserver15.xa.
+@       NS      ns1
+ns1     A     127.17.15.34
+ns1     AAAA  fda1:b2:c3:0:127:17:15:34
+
+$ORIGIN no-version-revealed-5.nameserver15.xa.
+@       NS      ns1
+ns1     A     127.17.15.35
+ns1     AAAA  fda1:b2:c3:0:127:17:15:35
+
+$ORIGIN no-version-revealed-6.nameserver15.xa.
+@       NS      ns1
+ns1     A     127.17.15.36
+ns1     AAAA  fda1:b2:c3:0:127:17:15:36
+
+$ORIGIN error-on-version-query-1.nameserver15.xa.
+@       NS      ns1
+ns1     A     127.17.15.37
+ns1     AAAA  fda1:b2:c3:0:127:17:15:37
+
+$ORIGIN error-on-version-query-2.nameserver15.xa.
+@       NS      ns1
+ns1     A     127.17.15.38
+ns1     AAAA  fda1:b2:c3:0:127:17:15:38
+
+$ORIGIN software-version-1.nameserver15.xa.
+@       NS      ns1
+ns1     A     127.17.15.39
+ns1     AAAA  fda1:b2:c3:0:127:17:15:39
+
+$ORIGIN software-version-2.nameserver15.xa.
+@       NS      ns1
+ns1     A     127.17.15.40
+ns1     AAAA  fda1:b2:c3:0:127:17:15:40
+
+$ORIGIN wrong-class-1.nameserver15.xa.
+@       NS      ns1
+ns1     A     127.17.15.41
+ns1     AAAA  fda1:b2:c3:0:127:17:15:41
+
+$ORIGIN wrong-class-2.nameserver15.xa.
+@       NS      ns1
+ns1     A     127.17.15.42
+ns1     AAAA  fda1:b2:c3:0:127:17:15:42
+
+
+; EOF