Integrate ddclient for easy DDNS support #5004
Description
As discussed in #4464, please add an integrated DDNS client.
Including ddclient in the docker container, with the ability to manage it from the Nginx Proxy Manager webui would be so useful. Most home users don't have a static IP so making DDNS really simple would be great.
Personally, the hardest part of entire setup of enabling remote access to my Audiobookshelf server was figuring out how to get ddclient working in a second docker container, so it could update the IP address of my Cloudflare-hosted domain. Nginx Proxy Manager made the rest really easy but it would have been so much easier if there was an entirely integrated solution.