New enum variant added after audit finds unnamed rollback refusal in agent pipeline

A code audit on August 31, 2026 discovered that one of eight construction sites for a rollback refusal value was missing a required cause, caught by a source-scan test named every_construction_of_the_third_value_names_its_cause. The affected site handled a postcondition mismatch — where a forward operation succeeded but the reported state digest disagreed with the plan's predicted outcome, prompting the engine to decline firing the escrowed inverse. None of the six existing enum variants accurately described this scenario without misrepresenting the facts, so a seventh variant, PromisedPostStateWasWrong, was introduced. Adding the new variant triggered three further test failures in sequence, as count-tracking and registry tests enforced that all changes be formally accounted for together. The fix required no wire-format upgrader changes, since the type never enters the journal or state root, and unknown diagnostic strings were already specified to default to a safe hold behavior.