Function forward_stop_pending 

async fn forward_stop_pending(
    state: &AppState,
    entry: &AgentEntry,
    block_id: &str,
    by: &str,
    signal: Option<&str>,
) -> Forwarded

A cross-channel FleetBulkStop target: ask ITS instance’s user (/agentmux/agent/stop-pending), whose banner, chime and Keep running are the ones that user sees. The request’s status is served from there; pending_shutdown::remember_remote lets this instance proxy it. An instance without that route (404) gets the plain forward it always did.