2026-07-11 final clean-gate audit
Command:
  export PATH="$HOME/.elan/bin:$HOME/.cargo/bin:$PATH" LEAN_NUM_THREADS=28
  ./check_answer/verify.sh
Result (exit 0):
  'Erdos321.erdos321_asymptotic' depends on axioms: [propext, Classical.choice, Quot.sound]
  PASS: faithful final asymptotic, all sources sorry-free, standard axioms only
