Requires spt-core **v0.39.1 or newer** and Oh My Pi **v16.3.15 or newer**. Update with `spt adapter update omp-spt`, then restart existing endpoints so they load the corrected extension.

### Fixed
- **Repeated messages from one sender retain one-to-one envelope custody across active turns.** Successive sender stubs now carry a per-sender delivery correlation, so a later context hook cannot attach a new envelope to the earlier request-local stub and leave the queued turn bare. This completes v0.3.17's atomic wake arbitration fix for the same-peer boundary case.