Feat: Adjust the style of the agent canvas connection line #3221 (#8922)

### What problem does this PR solve?

Feat: Adjust the style of the agent canvas connection line #3221

### Type of change


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

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

@@ -65,7 +65,7 @@ function InnerSwitchNode({ id, data, selected }: NodeProps<ISwitchNode>) {
   const { positions } = useBuildSwitchHandlePositions({ data, id });
   return (
     <ToolBar selected={selected} id={id} label={data.label}>
-      <NodeWrapper>
+      <NodeWrapper selected={selected}>
         <CommonHandle
           type="target"
           position={Position.Left}