Copilot CLI: failure recalls in subagents are recorded under the child session id #158

Copilot CLI fires postToolUse for subagent tool calls with the child session's id. A failure there injects a procedure recorded under that id, but the parser leaves subagent events out of the parent's trace, so the injection is never settled. Same problem as the Codex subagent one.

Applies to the agent support in #149.

Files:

• crates/trodden/src/harness/copilot.rs

Fix idea: don't recall on tool events from a session that isn't a root session (no events.jsonl of its own).