generator: with both saveTransient and in-place enabled, an error during generation leaves model vault in TransientModelsModule inconsistent (two models with same model reference). Refactor clean-up/publish code for transient models to (a) ensure proper vault state (b) expose last input and output models at the moment of failure. Drop FNF once transient model is gone to avoid memory leak (repo tracker in FNFM is not notified about transients models that are not in any repository).