fix: Share production uploads folder with staging

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Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

docker-compose.staging.yml

@@ -26,7 +26,7 @@ services:
     environment:
       - ENV=staging
     volumes:
-      - ./backend/uploads:/app/uploads
+      - /opt/autonet/production/backend/uploads:/app/uploads
       - /opt/autonet/production/backend/autonet.db:/app/autonet.db
     restart: unless-stopped
     networks: