NB: in order to produce correct IR origins, the source element kinds for
some FIR elements has been changed. As a side effect, mapping PSI to FIR
slightly changed: namely, for `a[b]++`, `a[b]` used to be mapped on
`set` call or callable reference, but now it is mapped on `get` call.
^KT-61891: Fixed
^KT-64387: Fixed
vladislav.grechko
9aa8fb80e7