feat: add WebDAV sync service for ComfyUI outputs

Add Python watchdog service to automatically sync ComfyUI outputs to HiDrive WebDAV storage.

Changes:
- Add scripts/comfyui_webdav_sync.py: File watcher service using watchdog + webdavclient3
- Update model-orchestrator/requirements.txt: Add watchdog and webdavclient3 dependencies
- Update supervisord.conf: Add webdav-sync program with ENV variable support
- Update arty.yml: Add service management scripts (start/stop/restart/status/logs)

WebDAV credentials are now loaded from .env file (WEBDAV_URL, WEBDAV_USERNAME, WEBDAV_PASSWORD, WEBDAV_REMOTE_PATH)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

arty.yml

@@ -327,6 +327,7 @@ scripts:
     echo "Services configured:"
     echo "  - comfyui: ComfyUI server (port 8188) - autostart enabled"
     echo "  - orchestrator: Model orchestrator (port 9000) - autostart disabled"
+    echo "  - webdav-sync: WebDAV output sync service - autostart enabled"
     echo ""
     echo "To start: supervisord -c /workspace/supervisord.conf"
     echo "To manage: supervisorctl status"
@@ -678,6 +679,13 @@ scripts:
   services/orchestrator/status: supervisorctl -c /workspace/supervisord.conf status ai-services:orchestrator
   services/orchestrator/logs: supervisorctl -c /workspace/supervisord.conf tail -f ai-services:orchestrator
 
+  # WebDAV Sync service
+  services/webdav-sync/start: supervisorctl -c /workspace/supervisord.conf start ai-services:webdav-sync
+  services/webdav-sync/stop: supervisorctl -c /workspace/supervisord.conf stop ai-services:webdav-sync
+  services/webdav-sync/restart: supervisorctl -c /workspace/supervisord.conf restart ai-services:webdav-sync
+  services/webdav-sync/status: supervisorctl -c /workspace/supervisord.conf status ai-services:webdav-sync
+  services/webdav-sync/logs: supervisorctl -c /workspace/supervisord.conf tail -f ai-services:webdav-sync
+
   #
   # Health Checks
   #