If you think it’s worth your time to correct this, I’d suggest looking into NGINX. There is a few ways to go about it that depends on the environment this running on…
Basically, if you can install NGINX on to something, you’d point the DNS record for ketogenicforums.com to that IP. Next, NGINX is configured to 301 redirect all ‘http://ketogenicforums.com’ to ‘https://www.ketogenicforums.com’.
If you had to put NGINX & Discourse on the same IP & server, it should be possible to have NGINX to proxy all traffic to Discourse (which could be setup on a firewalled, non standard port).
Since you are using https, you might need a wildcard cert rather then just a single sub domain cert if you want to redirect https://ketogenicforums.com to the full URL with out causing any warnings in the web browsers.