noobconner21/UDP-Custom-Script ? reverse-engineered prompt

Build me a simple shell based installer and menu for a 64 bit VPS that turns on UDP support and gives me an easy way to manage custom users and VPN tunnel settings for the HTTP Custom app.

I want one script I can run on a fresh server that sets everything up, then opens a menu when I type menu. From there I should be able to create users, view existing users, and manage them without having to edit files by hand. It should also handle the basic setup needed for the UDP custom service and make it usable with HTTP Custom.

Please make it work as a clean VPS tool, with clear prompts, sensible defaults, and enough checks so it does not break on a typical Debian or Ubuntu server. If anything depends on current package or app details, look up the latest docs online if you need to.