Optionalassembler: FeatureAssemblyExecutoroptional FeatureAssembly executor override (tests may inject one)
Train a model end-to-end from a pipeline definition.
the pipeline id + optional session-iteration / as-of inputs
the injected dependency bundle (entity factory, loader, sidecar, store)
the produced Draft model and the Completed/Failed training run
Training orchestrator. Stateless across calls; construct once and reuse. All dependencies are supplied per call via TrainingDeps.