- Update nginx config for HTTPS with Let's Encrypt certificates
- Add HTTP to HTTPS redirect
- Configure SSL security headers and HSTS
- Add Django HTTPS security settings for production
- Fix proxy_pass to use correct port 8081
- Enhance Content Security Policy for HTTPS
- Update settings.py to support both ALLOWED_HOSTS and DJANGO_ALLOWED_HOSTS
- Add production CSRF_TRUSTED_ORIGINS for vhtv-stiftung.de
- Update env-template.txt with production variable examples
- Improve compatibility between development and production environments