ReactFlow 连接线测试
如果看到3个节点和2条红色/绿色连接线，说明ReactFlow正常工作
Nodes: 3, Edges: 2
连接1→2
连接2→3
节点 1
节点 2
节点 3
React Flow
Press enter or space to select a node.You can then use the arrow keys to move the node around. Press delete to remove it and escape to cancel.
Press enter or space to select an edge. You can then press delete to remove it or escape to cancel.