Feat: Add a loop variable to the loop operator. #10427 (#11423)

### What problem does this PR solve?

Feat: Add a loop variable to the loop operator. #10427

### Type of change


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

web/src/pages/agent/canvas/index.less

@@ -8,4 +8,7 @@
     border: 0;
     background-color: transparent;
   }
+  :global(.react-flow__node-group.selectable.selected) {
+    box-shadow: none;
+  }
 }

web/src/pages/agent/canvas/node/iteration-node.tsx

@@ -8,7 +8,6 @@ import { memo } from 'react';
 import { NodeHandleId, Operator } from '../../constant';
 import OperatorIcon from '../../operator-icon';
 import { CommonHandle, LeftEndHandle } from './handle';
-import styles from './index.less';
 import NodeHeader from './node-header';
 import { NodeWrapper } from './node-wrapper';
 import { ResizeIcon, controlStyle } from './resize-icon';
@@ -23,9 +22,12 @@ export function InnerIterationNode({
   return (
     <ToolBar selected={selected} id={id} label={data.label} showRun={false}>
       <section
-        className={cn('h-full bg-transparent rounded-b-md group', {
-          [styles.selectedHeader]: selected,
-        })}
+        className={cn(
+          'h-full bg-transparent rounded-b-md group border border-border-button border-t-0',
+          {
+            ['border-x border-accent-primary']: selected,
+          },
+        )}
       >
         <NodeResizeControl style={controlStyle} minWidth={100} minHeight={50}>
           <ResizeIcon />
@@ -43,9 +45,9 @@ export function InnerIterationNode({
           name={data.name}
           label={data.label}
           wrapperClassName={cn(
-            'bg-background-header-bar p-2 rounded-t-[10px] absolute w-full top-[-44px] left-[-0.3px]',
+            'bg-background-header-bar p-2 rounded-t-[10px] absolute w-full top-[-38px] left-[-0.3px] border-x border-t border-border-button',
             {
-              [styles.selectedHeader]: selected,
+              ['border-x border-t border-accent-primary']: selected,
             },
           )}
         ></NodeHeader>