Add ntfy installation script

This script installs the ntfy notification service and its dependencies, sets up the necessary repository, and performs cleanup after installation.

install/ntfy-install.sh

@@ -0,0 +1,36 @@
+#!/usr/bin/env bash
+
+# Copyright (c) 2021-2025 tteck
+# Author: tteck (tteckster)
+# License: MIT | https://github.com/community-scripts/ProxmoxVE/raw/main/LICENSE
+# Source: https://ntfy.sh/
+
+source /dev/stdin <<<"$FUNCTIONS_FILE_PATH"
+color
+verb_ip6
+catch_errors
+setting_up_container
+network_check
+update_os
+
+msg_info "Installing Dependencies"
+$STD apt-get install -y \
+  apt-transport-https
+msg_ok "Installed Dependencies"
+
+msg_info "Installing ntfy"
+mkdir -p /etc/apt/keyrings
+curl -fsSL https://archive.heckel.io/apt/pubkey.txt | gpg --dearmor -o /etc/apt/keyrings/archive.heckel.io.gpg
+echo "deb [arch=amd64 signed-by=/etc/apt/keyrings/archive.heckel.io.gpg] https://archive.heckel.io/apt debian main" >/etc/apt/sources.list.d/archive.heckel.io.list
+$STD apt-get update
+$STD apt-get install -y ntfy
+systemctl enable -q --now ntfy
+msg_ok "Installed ntfy"
+
+motd_ssh
+customize
+
+msg_info "Cleaning up"
+$STD apt-get -y autoremove
+$STD apt-get -y autoclean
+msg_ok "Cleaned"