What kind of service do I need to be running in order to host the browser interface?
It runs as its own service. There's a Makefile that installs everything, and then you can start it with systemctl. It uses NodeJS, and it also needs a dgamelaunch installation.
What is your provider, how much does it cost? Do you pay extra to have static IP?
I use Linode, currently a $20/month plan, but the $10 package could easily handle it. IP addresses are static. Digital Ocean is another similar provider. Places that charge $5 or less tend to be unreliable.
Tournaments aren't too difficult technically, but getting players to show up can be hard. Giving everyone the same dungeon is an interesting idea. It would make the randomness affect everyone fairly and equally. But if people watched someone else's game, they could know in advance where monsters and treasure are.
By the way, I appreciate your help. Thanks.
Glad to give it. Happy hacking.