fix preview and save on native

frontend/src/workflowHydration.js

@@ -0,0 +1,52 @@
+function mergeDefinition(nodeData, defs) {
+  const savedData = nodeData || {};
+  const savedDefinition = savedData.definition && typeof savedData.definition === 'object'
+    ? savedData.definition
+    : null;
+  const registryDefinition = savedData.className ? defs[savedData.className] : null;
+  const definition = registryDefinition || savedDefinition;
+
+  if (!definition) return null;
+
+  const output = Array.isArray(savedData.output)
+    ? savedData.output
+    : (Array.isArray(savedDefinition?.output) ? savedDefinition.output : null);
+  const outputName = Array.isArray(savedData.output_name)
+    ? savedData.output_name
+    : (Array.isArray(savedDefinition?.output_name) ? savedDefinition.output_name : null);
+
+  return {
+    ...definition,
+    ...(output ? { output } : {}),
+    ...(outputName ? { output_name: outputName } : {}),
+  };
+}
+
+export function hydrateWorkflowState(data, defs = {}) {
+  const loadedNodes = Array.isArray(data?.nodes) ? data.nodes : [];
+  const loadedEdges = Array.isArray(data?.edges) ? data.edges : [];
+
+  const nodes = loadedNodes.map((node) => ({
+    ...node,
+    type: node.type || 'custom',
+    dragHandle: node.dragHandle || '.drag-handle',
+    data: {
+      ...node.data,
+      label: node.data?.label || node.data?.className || 'Node',
+      widgetValues: node.data?.widgetValues || {},
+      definition: mergeDefinition(node.data, defs),
+      previewImage: null,
+      tableRows: null,
+      meshData: null,
+      overlay: null,
+    },
+  }));
+
+  const nextNodeId = Math.max(0, ...loadedNodes.map((node) => parseInt(node.id, 10) || 0)) + 1;
+
+  return {
+    nodes,
+    edges: loadedEdges,
+    nextNodeId,
+  };
+}