Support NSIS muti-user (non-admin) installs
Currently, the installer (in setup.nsi) uses RequestExecutionLevel admin
which causes installation to fail if admin privileges are unavailable.
If instead MULTIUSER_EXECUTIONLEVEL Highest
is used, the installer can request admin privileges but fall back to current user installation.
See examples:
- https://nsis.sourceforge.io/Examples/MultiUser.nsi
- https://stackoverflow.com/questions/47162998/customize-instdir-according-to-currentuser-allusers-install-modes-in-nsis
More details on this feature can be found here.
If there is upstream interest in this, I would be willing to contribute.