- Replaced README.md with a modern, production-focused version featuring quick start, architecture, workflow, troubleshooting, and security sections
- Added DEPLOYMENT_GUIDE_IIS_Windows11.md with step-by-step IIS deployment instructions, including SSL, CORS, and permissions
- Added version-controlled web.config files for API and Blazor app with HTTPS redirection, security headers, and SPA/static file support
- Moved detailed yt-dlp integration notes to README_UPDATED.md for technical reference
- Improves clarity, maintainability, and production readiness of documentation and deployment