feat(deployment): support sse notification streaming

README.md

@@ -31,3 +31,11 @@ docker compose up --build
 ```
 
 The backend container runs database migrations and `collectstatic` on startup, then serves Django with Gunicorn using `config.wsgi:application`.
+
+## SSE Notifications
+
+Notifications now use Server-Sent Events at `/api/notifications/stream/`.
+
+- Nginx disables buffering and cacheing for the SSE endpoint.
+- The current Gunicorn setup can serve SSE for MVP traffic, but each live stream consumes a worker while connected.
+- If notification concurrency grows, move the SSE endpoint to an async worker class or a dedicated ASGI process.