GV123 unclosable-bootstrap counterexample

During human review of PR #53, Govenv already had a governed from-zero curriculum and could render every bootstrap challenge, but the shell only told the principal to preserve a response later in a pull request. There was no governed operation that captured the exact human response into canonical learning evidence, so the newly introduced gate was not operationally reachable from zero.

GV123 closes that hole with govenv-learning answer <key>, a dedicated Govenv.LearningEvidence authority, and an evidence-only candidate path whose only substantive source change may be that evidence authority and whose governed debt count must strictly decrease.

{-# OPTIONS --safe #-}

module Govenv.Assurance.GV123.Counterexample.UnclosableBootstrap where

open import Agda.Builtin.Bool using (true; false)
open import Agda.Builtin.Equality using (_≡_; refl)
open import Govenv.Kernel.Learning using (learningEvidenceCandidateAllowed)

renderingWithoutEvidenceProgressCannotCloseDebt :
  learningEvidenceCandidateAllowed true   ≡ false
renderingWithoutEvidenceProgressCannotCloseDebt = refl

unrelatedSemanticChangeCannotUseEvidencePath :
  learningEvidenceCandidateAllowed false   ≡ false
unrelatedSemanticChangeCannotUseEvidencePath = refl