I have a monorepo with a Next.js project in a next directory. I have other shared JS packages in a packages directory. All of this is configured correctly with package.json and tsconfig.json. Everything builds successfully with and without output: "standalone".

Except in standalone mode, the .next/standalone output directory seems to contain a complete copy of my monorepo. Even files that have nothing to do with the Next.js build (aka *.backup files, deploy scripts, other code projects, etc). The Next.js documentation claims to use a sophisticated algorithm to trace code paths and only include what's needed to run the app. What is happening here? How do I even go about debugging this issue?