inspect_keyed_archive reported caller selection failures as artifact
faults. A missing named root became "Artifact is invalid or has changed.
Get a fresh copy" and lost its reason, and a missing, non-canonical, or
directory archive path became "unsafe or conflicting internal path ...
correct the artifact".
Report these as invalid_request issues on `path` or `root`, listing the
available $top roots or the active plist basename. Decode failures keep
the decoder's reason, and a compiled NIBArchive points to
decode_interface_builder.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>