The launcher installs and updates PdfCraft with `msiexec /passive` and no properties, so
INSTALLDESKTOPSHORTCUT always took its default of 1 and every update put the shortcut back,
even for users who had deleted it. The property no longer has a static default: a SetProperty
after AppSearch turns it on for a first install, and for an update only while PdfCraft.lnk is
still on the all-users desktop. A value on the command line still wins, and the full-UI
checkbox still starts ticked on a first install.
test-msi.ps1 checks the action runs after AppSearch in both sequences and evaluates its
condition for first installs, updates with and without the shortcut, and
INSTALLDESKTOPSHORTCUT=0.
91c0b93c7f