Fix guacd debug logging: use env var instead of command override

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

docker-compose.yml

@@ -19,8 +19,8 @@ services:
   guacd:
     image: guacamole/guacd:1.5.4
     restart: unless-stopped
-    # -L debug gives full FreeRDP error detail in `docker logs mremotify-guacd-1`
-    command: ["/bin/sh", "-c", "/usr/local/sbin/guacd -b 0.0.0.0 -l 4822 -f -L debug"]
+    environment:
+      GUACD_LOG_LEVEL: debug
     networks:
       - internal