Feat: Convert the arguments parameter of the code operator to a dictionary #3221 (#8623)

### What problem does this PR solve?

Feat: Convert the arguments parameter of the code operator to a
dictionary #3221

### Type of change


- [x] New Feature (non-breaking change which adds functionality)

web/src/pages/agent/form/components/prompt-editor/variable-node.tsx

@@ -37,7 +37,7 @@ export class VariableNode extends DecoratorNode<ReactNode> {
     let content: ReactNode = (
       <span className="text-blue-600">{this.__label}</span>
     );
-    if (this.__value.startsWith(prefix)) {
+    if (this.__value?.startsWith(prefix)) {
       content = (
         <div>
           <span>{i18n.t(`flow.begin`)}</span> / {content}

web/src/pages/agent/form/components/prompt-editor/variable-picker-plugin.tsx

@@ -220,6 +220,10 @@ export default function VariablePickerMenuPlugin({
       }
 
       $getRoot().clear().append(paragraph);
+
+      if ($isRangeSelection($getSelection())) {
+        $getRoot().selectEnd();
+      }
     },
     [findLabelByValue],
   );