Add installer packaging and Winux discovery coverage

[caomengxuan666]

Summary

• add Inno Setup based installer packaging and release upload flow
• restore Winux installer and WinGet discovery in the PowerShell wrapper
• add PowerShell tests for installer root and WinGet package discovery

Verification

• powershell -NoProfile -ExecutionPolicy Bypass -File tests/scripts/winux_activate_profile_cleanup_test.ps1
• powershell -NoProfile -ExecutionPolicy Bypass -File tests/scripts/winux_command_discovery_test.ps1
• powershell -NoProfile -ExecutionPolicy Bypass -File tests/scripts/winux_winget_discovery_test.ps1
• powershell -NoProfile -ExecutionPolicy Bypass -File tests/scripts/winux_installer_root_discovery_test.ps1
• powershell -NoProfile -ExecutionPolicy Bypass -File scripts/build-installer.ps1 -Root C:\Users\cmx\repo\WinuxCmd -Arch x64 -IsccPath 'C:\Users\cmx\tools\Inno Setup 6\ISCC.exe'