thedevs-network/kutt ? reverse-engineered prompt

Build me a modern self hosted URL shortener that feels polished and simple to run. I want people to be able to create short links, optionally pick a custom short code, add a password, description, and expiration date, and use custom domains for links. Users should be able to sign in, manage their own links, and see private stats for each short URL. There should also be an admin area where I can manage users and links.

Please make the setup easy, with a sensible default local database so it works out of the box, but keep it configurable so someone can switch to a bigger database and optional cache later. I also want basic environment based config for things like the site name, default domain, registration settings, anonymous link creation, and login options. On first startup it should guide me to create an admin account.

It would be great if this runs both locally and with Docker, and includes a clean API for creating and managing links. If anything is unclear, check the current docs online and keep it close to the existing Kutt style and behavior.