fix(appd): remove abort_sender on READY timeout early-return path

The READY timeout branch killed the process and returned Ok(()) without
calling remove_abort_sender(), leaving a spent entry in abort_senders.
Add the call to keep it consistent with all other exit paths.

crates/weft-appd/src/runtime.rs

@@ -248,6 +248,7 @@ pub(crate) async fn supervise(
             kill_portal(portal).await;
             let mut reg = registry.lock().await;
             reg.set_state(session_id, AppStateKind::Stopped);
+            reg.remove_abort_sender(session_id);
             let _ = reg.broadcast().send(Response::AppState {
                 session_id,
                 state: AppStateKind::Stopped,