Release for Linux (downloadable package)

[anton-makarevich]

Sub-issue of #76

High-level tasks:

• Configure Linux build configuration (AppImage, deb, rpm)
• Set up Linux-specific dependencies and runtime
• Create installation scripts/packages
• Test on major Linux distributions (Ubuntu, Fedora, Arch)
• Set up Linux build pipeline (CI/CD)
• Create desktop entry file (.desktop)
• Handle Linux file system paths and permissions
• Consider Flatpak/Snap packaging for wider distribution
• Create release documentation for Linux users