Subagents stay in the foreground while a solo tool call waits behind them

A subagent is a helper Claude starts to work on part of a task. Claude Code can move a running subagent to the background automatically so other work carries on. Some tool calls (actions Claude takes) must run on their own, with nothing else running at the same time.

Now, when such a tool call is waiting behind a subagent, that subagent is not moved to the background automatically. A debug note is written once. If Claude's reply is still coming in, Claude Code checks again a little later.