Fix run recipe: optional fields in RunStatus, list->dict nodes

- Made recipe and inputs optional in RunStatus model
- Convert DAG nodes from list format to dict format when running recipes

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/routers/recipes.py

@@ -220,6 +220,16 @@ async def run_recipe(
             dag_copy = json.loads(json.dumps(recipe_dag))  # Deep copy
             nodes = dag_copy.get("nodes", {})
 
+            # Convert nodes from list to dict if needed
+            if isinstance(nodes, list):
+                nodes_dict = {}
+                for node in nodes:
+                    node_id = node.get("id")
+                    if node_id:
+                        nodes_dict[node_id] = node
+                nodes = nodes_dict
+                dag_copy["nodes"] = nodes
+
             # Map input names to content hashes
             for input_name, content_hash in req.inputs.items():
                 if input_name in nodes: