Ok, I took a look at your project, and what I think may be happening. Your project is configured to use pnpm as its package manager and I think when you run npm install serve you’re running into a collision between using pnpm and npm on the same project.
I executed enable-pnpm in your project’s console and that forced a new installation of everything in your package.json file and everything seems to have aligned itself more successfully and you project appears to have started correctly.
If you’d prefer to use npm then you can run enable-npm and that will switch your project to npm, but keep in mind that that means your packages will take up disk space in your project.
Sorry for the bother!