chore(examples): add old api examples

example/src_oldapi/UseUpdateNodeInternals/CustomNode.tsx

@@ -0,0 +1,34 @@
+import React, { memo, FC, useMemo, CSSProperties } from 'react';
+
+import { Handle, Position, NodeProps } from 'react-flow-renderer';
+
+const nodeStyles: CSSProperties = { padding: 10, border: '1px solid #ddd' };
+
+const CustomNode: FC<NodeProps> = ({ data }) => {
+  const handles = useMemo(
+    () =>
+      Array.from({ length: data.handleCount }, (x, i) => {
+        const handleId = `handle-${i}`;
+        return (
+          <Handle
+            key={handleId}
+            type="source"
+            position={Position.Right}
+            id={handleId}
+            style={{ top: 10 * i + data.handlePosition * 10 }}
+          />
+        );
+      }),
+    [data.handleCount, data.handlePosition]
+  );
+
+  return (
+    <div style={nodeStyles}>
+      <Handle type="target" position={Position.Left} />
+      <div>output handle count: {data.handleCount}</div>
+      {handles}
+    </div>
+  );
+};
+
+export default memo(CustomNode);