- Make app cross-platform compatible (Windows, Linux, macOS)
- Replace CUPS-only printer detection with platform-aware code
- Add Windows printer support using win32print/win32api
- Add macOS printer support using lpstat
- Keep Linux CUPS support
- Add requirements_windows.txt for Windows installation
- Add comprehensive WINDOWS_SETUP.md guide
- Fallback to PDF output on all platforms
- Tested on Linux, ready for Windows/macOS