Background helper agent notifications go to the main agent instead of being dropped

A subagent is a helper agent that Claude starts to work on part of a task, sometimes in the background. Such an agent can have task notifications waiting for it, which are messages about work that has finished.

Before, if the helper agent failed to wake up because of a resume error, those notifications were dropped. Now, as long as you did not stop the agent yourself, they are handed to the main agent instead.

When a recorded helper agent is resumed, Claude Code also keeps track of a question it was waiting on. If the resume never happens, that question is closed and marked as "not_resumed".