even MORE code review

stateful to not deadhang, graph context -> output, more explicit state errors, other misc changes idfk any of those good thing theyre fixed tho

src/wf_core/runtime/foreach_state.py

@@ -363,8 +363,10 @@ def _state_write_from_metadata(raw: object) -> StateWrite:
             visible_value=visible_value,
             reducer=ReducerRef.model_validate(reducer),
         )
-    except Exception as exc:
-        raise WorkflowExecutionError("malformed pending foreach write") from exc
+    except WorkflowExecutionError:
+        raise
+    except (TypeError, ValueError) as exc:
+        raise WorkflowExecutionError(f"malformed pending foreach write: {exc}") from exc
 
 
 def _state_write_to_metadata(write: StateWrite) -> dict[str, Any]:

src/wf_core/runtime/lineage.py

@@ -216,7 +216,13 @@ def _lineage_chain(
 ) -> Iterator[LineageState]:
     lineage = _lineage(run, scope_id=scope_id, lineage_id=lineage_id)
     reverse_chain: list[LineageState] = []
+    seen: set[str] = set()
     while True:
+        if lineage.id in seen:
+            raise WorkflowExecutionError(
+                f"cycle detected in lineage chain at {lineage.id!r}"
+            )
+        seen.add(lineage.id)
         reverse_chain.append(lineage)
         if lineage.parent_id is None:
             break

src/wf_core/runtime/subgraphs.py

@@ -253,6 +253,7 @@ def _finish_subgraph(
         prepared.workflow,
         child_scope.committed_state,
         workflow_input=child_scope.workflow_input,
+        context=frame_context_values(child_frame),
     )
     validate_payload_against_schema(
         prepared.workflow.output_schema,