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- add `ZEN_MEDIA` env flag and document it in `.env.example` - add media schema, server routes, and API handlers (`api.server.js`, `routes.server.js`, `schema.server.js`) - add `MediaPage`, `MediaGrid`, `MediaFilters`, and `MediaPicker` client components - expose `@zen/core/features/media` and `@zen/core/features/media/picker` package exports - register media navigation and permissions; wire module into `init.js` - document media API, client picker usage, and boundary rules in `MODULES.md` and `ARCHITECTURE.md` - add `src/features/media/README.md`