## What changed
- Project durable paginated rollout records into rebuildable SQLite tables for turns, items, and projection progress while keeping JSONL as the source of truth.
- Add cursor-based local reads for turn summaries and thread or per-turn items, including archived-thread and history-mode validation.
- Serialize writes, shutdown, and deletion per thread so projection updates cannot race cleanup, and remove projected rows when a thread is deleted.
- Preserve stable item ordering while updating repeated snapshots and expose structured turn error details.
## Testing
- Cover projection, snapshot updates, summary recovery, pagination, failure handling, shutdown flushing, legacy-mode rejection, and deletion races.
GitOrigin-RevId: 34533185ece7f1f5690004c7f12b0f1f34dc2640