Integrates #3697 on current main. Prefer the observer project ID, retain a sole legacy ID until the new observer folder exists, and release the ending session lease across same-root aliases. Replace the unsafe live merge hint with read-only project inspection, and validate alias IDs before path use. #3711 independently identified the computed-ID selection gap; its early switch without observer data and unchanged SessionEnd path were not adopted.
- session-end-marker.js now exports run() function
- Enables in-process execution via run-with-flags.js
- Avoids spawnSync cross-platform issues on Windows
- Maintains backward compatibility with direct CLI execution
Fixes#429
Co-authored-by: 阳虎 <yanghu@yanghudeMacBook-Pro.local>