#fs

Deliberately re-cause the build failure from server-module-client-bundle: two lines in lib/tracks.ts, one of which is the line that actually matters. Capture the import trace, then revert.

lib/tracks.ts imported fs and path at the top level. track-roadmap.tsx (a 'use client' component) imported from lib/tracks.ts, pulling Node.js modules into the browser bundle. Build failed with Module not found: Can't resolve 'fs'.