Function parent_tool_results_at 

pub(super) fn parent_tool_results_at(
    parent_jsonl: &Path,
) -> HashMap<String, bool>

Read an already-resolved parent transcript. An unreadable/absent file yields an empty map, which makes terminal_status fall back to the old Abandoned inference — conservative, and identical to pre-fix behaviour.

Takes the resolved path rather than a subagent path so the caller can cache one read per distinct parent: members of a reconcile pass do not all resolve to the same transcript (see parent_transcript_for), so resolving once from an arbitrary member and reusing it for the rest is wrong — that was reagent’s P1 on #3007.