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>

requirements.txt

@@ -13,9 +13,11 @@ python-multipart==0.0.6
 httpx==0.26.0
 jinja2==3.1.2
 docker==7.0.0
+requests<2.32.0
 urllib3<2
 psutil==5.9.7
 pyyaml==6.0.1
+msal==1.28.0
 pytest==7.4.3
 pytest-asyncio==0.23.2
 pytest-httpx==0.28.0