the /usr/bin/krunner
executable is owned by the plasma-workspace
package. It has a lot of dependencies. So yeah, you basically need a huge chunk of kde/plasma to run it.
A pretty similar Qt-based launcher utility (not quite so good in some areas, possibly better in some) is called albert, if you don't want to use plasma anymore.
Here is the study, "Assessment of Stoichiometric Autocatalysis across Element Groups", linked in the last paragraph of the article for your enjoyment: https://pubs.acs.org/doi/10.1021/jacs.3c07041