feat: Add hint for operators, round to square, input variable, readable operator ID. #3056 (#3057)

### What problem does this PR solve?

feat: Add hint for operators, round to square, input variable, readable
operator ID. #3056

### Type of change

- [ ] Bug Fix (non-breaking change which fixes an issue)
- [x] New Feature (non-breaking change which adds functionality)
- [ ] Documentation Update
- [ ] Refactoring
- [ ] Performance Improvement
- [ ] Other (please describe):

web/src/pages/flow/canvas/node/message-node.tsx

@@ -0,0 +1,63 @@
+import { Flex } from 'antd';
+import classNames from 'classnames';
+import { get } from 'lodash';
+import { Handle, NodeProps, Position } from 'reactflow';
+import { NodeData } from '../../interface';
+import { LeftHandleStyle, RightHandleStyle } from './handle-icon';
+import styles from './index.less';
+import NodeHeader from './node-header';
+import NodePopover from './popover';
+
+export function MessageNode({
+  id,
+  data,
+  isConnectable = true,
+  selected,
+}: NodeProps<NodeData>) {
+  const messages: string[] = get(data, 'form.messages', []);
+
+  return (
+    <NodePopover nodeId={id}>
+      <section
+        className={classNames(styles.logicNode, {
+          [styles.selectedNode]: selected,
+        })}
+      >
+        <Handle
+          id="c"
+          type="source"
+          position={Position.Left}
+          isConnectable={isConnectable}
+          className={styles.handle}
+          style={LeftHandleStyle}
+        ></Handle>
+        <Handle
+          type="source"
+          position={Position.Right}
+          isConnectable={isConnectable}
+          className={styles.handle}
+          style={RightHandleStyle}
+          id="b"
+        ></Handle>
+        <NodeHeader
+          id={id}
+          name={data.name}
+          label={data.label}
+          className={classNames({
+            [styles.nodeHeader]: messages.length > 0,
+          })}
+        ></NodeHeader>
+
+        <Flex vertical gap={8} className={styles.messageNodeContainer}>
+          {messages.map((message, idx) => {
+            return (
+              <div className={styles.nodeText} key={idx}>
+                {message}
+              </div>
+            );
+          })}
+        </Flex>
+      </section>
+    </NodePopover>
+  );
+}