can_dynamic_batch only inspects request fields, but several shipped
pipelines are structurally batch-size-1 and can corrupt outputs when
requests are merged. Add PipelineConfig.supports_dynamic_batching
(default False) with dynamic_batching_supported() as the effective
gate: the Wan family opts in (the generic Wan denoising path is the
verified parity target), while DMD and causal denoising variants are
always vetoed because those stages do not consume per-item generators
and merged requests would share RNG. The scheduler refuses to start and
_generate_prepared_work_items refuses to merge with a clear error when
the loaded pipeline has not opted in.
SolitaryThinker
efc53ba93b