fix: resolve Next.js docker build endpoints and handle async map icons

docker-compose.yml

@@ -19,11 +19,13 @@ services:
   frontend:
     build:
       context: ./frontend
+      args:
+        # Optional: set this to your backend's external URL if using custom ports
+        # e.g. http://192.168.1.50:9096 — leave empty to auto-detect from browser
+        NEXT_PUBLIC_API_URL: ${NEXT_PUBLIC_API_URL:-}
     container_name: shadowbroker-frontend
     ports:
       - "3000:3000"
-    environment:
-      - NEXT_PUBLIC_API_URL=http://localhost:8000
     depends_on:
       - backend
     restart: unless-stopped