"""Cache-method ports for the HY-WorldPlay (HunyuanVideo-1.5 AR, 4-step distilled) base.

Same experiment as ``cachelib`` on Self-Forcing / Causal-Forcing, on a different
DiT: 54 double-stream blocks whose vision path attends to cached text K/V and
cached history-vision K/V.  Denoising forwards never write the KV cache
(``cache_vision=False``); the per-chunk context pass does.  So a cached step can
skip the whole block stack without leaving stale cache entries behind.
"""