feat(trajectory): D1 轨迹飞轮 — 汇聚标注 + SFT/DPO/GRPO 导出 (#50 #51) - #56

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/checkout@v4. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/