Under the hood
A missed subagent transcript read now triggers on-demand hydration and a retry before reporting it unresumable.
Fetching a subagent's transcript now first tries a fast local read, and if that misses for a reason other than a load-time throw with no partial content found, it triggers on-demand hydration and retries. If it still fails, it logs a structured agent_transcript_unresumable warning with the specific miss reason.