TL;DR: Stop throwing everything into components/. After 6 production apps and 3 burned-out refactors, I landed on a feature-based, domain-driven structure that scales from 1 to 100 components. I have tried every structure: grouped by type, grouped by route, atomic design, and even "just throw it in src." This is the one that finally made me stop crying during code reviews. The Golden Rule: Co-location of Concern "Files that change together, live together." If you are editing UserProfile.tsx and you have to jump to 4 different folders (components/, hooks/, types/, services/), your structure is broken.…