fix: qbittorrent mem limit

arr-stack/docker-compose.yaml

@@ -16,6 +16,10 @@ services:
       - 8019:6881/udp # BitTorrent UDP port
       - 8020:9865/tcp # Additional port mapping
     restart: unless-stopped
+    deploy:
+      resources:
+        limits:
+          memory: 3000M # limit runaway RAM usage
 
   prowlarr:
     image: linuxserver/prowlarr