The mint went through one atom per environment, refreshed and then read on
every call, so two overlapping answers could both receive the same one-use
code and one link failed with the code already spent. Minting now runs as an
environment command, which builds a fresh effect for every call, shared by
web and mobile through client-runtime.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>