fix(loop): 修复子工作流循环节点层级丢失

[openjiuwen-sync-bot]

Paired: GitHub #158 ↔ GitCode !1752

fix(loop): 修复子工作流循环节点调用链层级丢失

新版工作流引擎将循环体节点的 parentNodeId 表示为
“子工作流节点.循环节点”，事件转换层又在检测到 loopNodeId 时
清空 parentNodeId，导致循环体节点被前端错误展示在父工作流根级。

• 从父节点路径中移除末尾循环节点，恢复所属子工作流节点 ID
• 将 loopIndex 从 0-based 转换为兼容旧版契约的 1-based
• 在 node_started 和 node_finished 事件中保留 loopNodeId、loopIndex
• 保持 parentInvokeId 使用引擎原始值，避免生成自引用调用关系
• 补充循环层级转换和事件元数据映射的回归测试

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head_sha: 5f9344b2a25e58ef37afed8db72710e7539cb2e4

TASK	STATUS	DETAILS
CodeCheck	✅SUCCESS	Click here
AntiPoison	✅SUCCESS	Click here
Software Composition Analysis	✅SUCCESS	Click here
Npm Build	✅SUCCESS	See CHECK tab
Ruff Check	✅SUCCESS	See CHECK tab
UT测试	✅SUCCESS	点此跳转