[rd-code-23]

Summary

Reorganizes the Express backend around product features so its high-level structure matches the frontend's feature-based organization and the architecture already documented for GoForLift.

This is a structure-only refactor. Routes, contracts, database behavior, authentication behavior, and API responses are unchanged.

What changed

• Moved apps/api/src/auth to apps/api/src/features/auth.
• Moved apps/api/src/exercises to apps/api/src/features/exercises.
• Updated imports affected by the additional features directory level.
• Updated server.ts composition-root imports to use the new feature paths.
• Kept config, db, and test at the API source root because they support multiple features and are shared infrastructure.

Resulting structure

apps/api/src/
├── features/
│   ├── auth/
│   │   ├── csrf/
│   │   ├── google/
│   │   ├── guards/
│   │   ├── session/
│   │   └── user/
│   └── exercises/
├── config/
├── db/
├── test/
├── app.ts
├── app.test.ts
└── server.ts

Why this structure

auth and exercises represent product capabilities, so grouping them under features makes feature ownership visible at a glance and keeps related routes, services, middleware, and tests together.

config, db, and test remain outside features because they are shared infrastructure. Moving them under a specific feature would imply ownership that they do not have.

This also makes the API consistent with the existing architectural guidance in AGENTS.md and docs/architecture.md. No documentation changes were necessary because both files already prescribe this organization.

Behavioral impact

None. Git recognizes all 18 source-file changes as moves, with only relative import paths adjusted. Endpoint URLs remain:

• /auth/*
• /exercises
• /health

Verification

• Type-checking passed.
• ESLint passed.
• All 74 tests passed.
• Formatting passed for all moved and modified files.