Add CoreDNS DNS server scripts

- ct/coredns.sh: CT script with update support
- install/coredns-install.sh: Install script with default Corefile
- json/coredns.json: JSON metadata

Closes #9665

install/coredns-install.sh

@@ -0,0 +1,55 @@
+#!/usr/bin/env bash
+
+# Copyright (c) 2021-2026 community-scripts ORG
+# Author: CopilotAssistant (community-scripts)
+# License: MIT | https://github.com/community-scripts/ProxmoxVED/raw/main/LICENSE
+# Source: https://github.com/coredns/coredns
+
+source /dev/stdin <<<"$FUNCTIONS_FILE_PATH"
+color
+verb_ip6
+catch_errors
+setting_up_container
+network_check
+update_os
+
+fetch_and_deploy_gh_release "coredns" "coredns/coredns" "prebuild" "latest" "/usr/local/bin" \
+  "coredns_*_linux_$(dpkg --print-architecture).tgz"
+chmod +x /usr/local/bin/coredns
+
+msg_info "Configuring CoreDNS"
+mkdir -p /etc/coredns
+cat <<EOF >/etc/coredns/Corefile
+. {
+    forward . 1.1.1.1 1.0.0.1
+    cache 30
+    log
+    errors
+    health :8080
+    ready :8181
+}
+EOF
+msg_ok "Configured CoreDNS"
+
+msg_info "Creating Service"
+cat <<EOF >/etc/systemd/system/coredns.service
+[Unit]
+Description=CoreDNS DNS Server
+After=network.target
+
+[Service]
+Type=simple
+ExecStart=/usr/local/bin/coredns -conf /etc/coredns/Corefile
+Restart=on-failure
+RestartSec=5
+LimitNOFILE=1048576
+
+[Install]
+WantedBy=multi-user.target
+EOF
+systemctl enable -q --now coredns
+msg_ok "Created Service"
+
+motd_ssh
+customize
+cleanup_lxc