Welcome to the forum! The short answer to this is: “npm run build” is not a command in your package.json file. It looks like your command is “npm run build-run”:
So! Taking a quick look at your repo, it looks like you do have a server. To host on Netlify, you’d have to port your app to be serverless and set up a different database configuration to work with that. This blog post might be useful for you:
Let us know if we can answer any other questions about any of this!