Nav links were `hidden md:flex` with no mobile fallback — sub-768px viewports showed only logo + avatar, no way to reach Explore, Feed, Collections, etc. Add a Sheet-based hamburger menu with the same links.
App Router setup with next-intl (en/fr), Better Auth wiring, shadcn/ui components, Tailwind, AES-256-GCM encrypt util, Redis rate limiter, tier limit checker, site_settings helper for runtime .env overrides.
Arnaud