docs: note NextDNS exposes DNS on TCP/UDP 53

Surface port 53 in the CT success message, JSON description, and
install notes so operators know where to point clients after setup.
interface_port stays null (no local web UI).

Author: nberardi

ct/nextdns.sh

@@ -55,4 +55,5 @@ echo -e "${TAB}${DEFAULT}  -profile <your profile id> \\${CL}"
 echo -e "${TAB}${DEFAULT}  -report-client-info \\${CL}"
 echo -e "${TAB}${DEFAULT}  -setup-router${CL}"
 echo -e "${INFO}${YW}Get your profile ID from: https://my.nextdns.io${CL}"
-echo -e "${INFO}${YW}Container IP: ${BGN}${IP}${CL}"
+echo -e "${INFO}${YW}After configuration, DNS is exposed on:${CL}"
+echo -e "${GATEWAY}${BGN}${IP}:53${CL} ${YW}(TCP/UDP)${CL}"

json/nextdns.json

@@ -13,7 +13,7 @@
   "website": "https://nextdns.io/",
   "repository": "https://github.com/nextdns/nextdns",
   "logo": "https://cdn.jsdelivr.net/gh/selfhst/icons@main/webp/nextdns.webp",
-  "description": "NextDNS is a DNS-over-HTTPS (DoH) client and resolver that blocks ads, trackers and malware using cloud-managed profiles. This script installs a minimal Debian LXC with the official NextDNS CLI package from the NextDNS apt repository; you configure your profile after install.",
+  "description": "NextDNS is a DNS-over-HTTPS (DoH) client and resolver that blocks ads, trackers and malware using cloud-managed profiles. This script installs a minimal Debian LXC with the official NextDNS CLI package from the NextDNS apt repository; after you configure a profile it serves DNS on TCP/UDP port 53.",
   "install_methods": [
     {
       "type": "default",
@@ -42,7 +42,11 @@
       "type": "info"
     },
     {
-      "text": "Router mode (-setup-router) makes this LXC the DNS server for your network. Point DHCP clients at the container IP (shown after install), or set it as the upstream DNS on your router.",
+      "text": "After configuration, NextDNS listens on TCP/UDP port 53. Point DHCP clients at the container IP:53, or set the container as upstream DNS on your router. There is no local web UI (profiles are managed at my.nextdns.io).",
+      "type": "info"
+    },
+    {
+      "text": "Router mode (-setup-router) makes this LXC the DNS server for your network.",
       "type": "info"
     },
     {