They are mostly necessary for argument mapping during resolution.
To support a couple checkers, we transform named args for varargs
into "fake" spread expressions.
Other than that, named arguments aren't needed for anything and often
lead to bugs where we forget to unwrap them for something, so it's
better to get rid of them.
#KT-66124
If an annotation doesn't specify an explicit use-site target,
previously it was added to both, the primary constructor value parameter
and the property in the FIR. Then, in FIR2IR, only the "correct" one was
added to the IR. Move up the deduplication logic into the frontend.
^KT-56177 Fixed
Kirill Rakhman