fix(scanners): closes scanner coverage gaps and adds language package managers

[wgordon17]

Summary

• Adds computer_name and known_network_services fields for nix-darwin mapping readiness
• Fixes read_plist_safe to fall back to plutil for InvalidFileException, recovering NeXTStep-format and newer binary plist variants
• Adds pipx, cargo, npm global, go, and gem package listing with package-to-binary mapping to the package_managers scanner