Is there a way to stop it from starting or safely uninstalling Krunner in KDE edition?
Maybe not. Looking at the dependency tree, krunner is required by milou which in turn is required by plasma-workspace a.k.a. your desktop.
I don’t know if you can disable it when using KDE, but you can disable all shortcuts for it and you can go to its config (the button on the left) and uncheck all plugins.
Remove it’s executable bit.
sudo chmod -x /usr/bin/krunner
and then kill the running process.
dude, why would anyone delete krunner ?
itz a cool helper. except they removed the downarrow recently which was a crap move.