Add i18n, branding, user management, health checks, and cleanup for deployment

- Multi-language support (EN/DE) with i18n engine and language files
- Configurable branding (name, subtitle, logo) in Settings
- Global default language and per-user language preference
- User management router with CRUD endpoints
- Customer status sync on start/stop/restart
- Health check fixes: derive status from container state, remove broken wget healthcheck
- Caddy reverse proxy and dashboard env templates for customer stacks
- Updated README with real hardware specs, prerequisites, and new features
- Removed .claude settings (JWT tokens) and build artifacts from tracking
- Updated .gitignore for .claude/ and Windows artifacts

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

app/utils/config.py

@@ -30,6 +30,7 @@ class AppConfig:
     data_dir: str
     docker_network: str
     relay_base_port: int
+    dashboard_base_port: int
 
 
 # Environment-level settings (not stored in DB)
@@ -77,4 +78,5 @@ def get_system_config(db: Session) -> Optional[AppConfig]:
         data_dir=row.data_dir,
         docker_network=row.docker_network,
         relay_base_port=row.relay_base_port,
+        dashboard_base_port=getattr(row, "dashboard_base_port", 9000) or 9000,
     )