Dokumentacja na wejściu.
Kod na wyjściu.

## User Authentication

The system **shall** authenticate users
via OAuth 2.0 with PKCE flow.

Session timeout: 30 minutes.
Max concurrent sessions: 3.

auth.md
├── api-routes.md
├── db-schema.md
└── middleware.md
    └── rate-limit.md

auth.md           [changed]
├── api-routes.md  [updated]
├── db-schema.md   [updated]
└── middleware.md   [updated]
    └── rate-limit.md [updated]

export async function authenticate(
  req: Request
): Promise {
  const token = await verifyPKCE(req);
  return createSession(token, {
    timeout: 30 * 60,
    maxConcurrent: 3,
  });
}