@John Hewson user Thanks for reaching here! Azure Static Web Apps, purposely built for your Decentralized app (dApp), to GitHub Actions, Azure DevOps, and VSCode.
So, you can use Azure Static Web Apps to create a dApp and have your .dao domain resolve to it.
Refer to Quickstart: Building your first static site with Azure Static Web Apps
then you can follow the instructions to set up a custom domain with external providers in Azure Static Web Apps. You will need to create a CNAME record on your domain registrar account and then create a CNAME record in Azure Static Web Apps. You can also use Azure DNS to manage your domain name for Azure Static Web Apps, and then configure your domain name with the www subdomain. Once this procedure is complete, you can set up an apex domain.
Refer- Set up a custom domain in Azure Static Web Apps
Hope this helps. Let us know if issue remains.