fix(deploy): restore backend host binding for proxy connectivity

Keep Postgres restricted to localhost, but re-expose backend on host port 5001 so the external reverse proxy can reach API routes reliably.

Made-with: Cursor

docker-compose.yml

@@ -40,7 +40,7 @@ services:
       postgres:
         condition: service_healthy
     ports:
-      - "127.0.0.1:5001:5001"
+      - "5001:5001"
     healthcheck:
       test: ["CMD-SHELL", "wget -qO- http://localhost:5001/api/v1/health || exit 1"]
       interval: 30s