Add RDP debug logging and enable guacd debug level

- docker-compose: override guacd command with -L debug flag so FreeRDP
  errors are visible in `docker logs mremotify-guacd-1`
- rdp.ts: log RDP host/user, arg names, ready instruction, proxy-mode
  entry, and any error/disconnect instructions from guacd

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

docker-compose.yml

@@ -19,6 +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"]
     networks:
       - internal