fix depends for CacheList

src/exo/worker/engines/mlx/auto_parallel.py

@@ -294,7 +294,9 @@ def patch_pipeline_model[T](model: T, group: mx.distributed.Group) -> T:
 
         # Add dependency to last cache entry to ensure distributed ops are evaluated
         if cache is not None:
-            cache[-1].state = mx.depends(cache[-1].state, logits)  # type: ignore
+            last = cache[-1]  # type: ignore
+            dep_cache = last[0] if hasattr(last, "caches") else last  # type: ignore
+            dep_cache.keys = mx.depends(dep_cache.keys, logits)  # type: ignore
 
         return logits
 
@@ -320,7 +322,9 @@ def patch_tensor_model[T](model: T) -> T:
 
         # Add dependency to last cache entry to ensure distributed ops are evaluated
         if cache is not None and len(cache) > 0:  # pyright: ignore[reportAny]
-            cache[-1].state = mx.depends(cache[-1].state, logits)  # pyright: ignore[reportAny,reportUnknownMemberType]
+            last = cache[-1]  # pyright: ignore[reportAny]
+            dep_cache = last[0] if hasattr(last, "caches") else last  # pyright: ignore[reportAny]
+            dep_cache.keys = mx.depends(dep_cache.keys, logits)  # pyright: ignore[reportAny,reportUnknownMemberType]
 
         return logits