fix: name the realized constant in the missing `enableRealizationsForConst` error

This PR makes `realizeConst` report the constant being realized when `enableRealizationsForConst` has not been called for its target, instead of the mangled private name of the internal key type that the generic `realizeValue` check can only show.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
2 files changed