Execution errors are missing in the `executed` signal

[krassowski]

In upstream JupyterLab code KernelError information is included when execution fails

https://github.com/jupyterlab/jupyterlab/blob/653c22621f996249862093d0bb0f23b1279b0f52/packages/notebook/src/cellexecutor.ts#L94-L129

try {
  const reply = await CodeCell.execute(
    cell as CodeCell
    // ...
  );
  // ...

  ran = (() => {
    // ...
    if (reply.content.status === 'ok') {
      // ...
      return true;
    } else {
      throw new KernelError(reply.content);
    }
  })();
} catch (reason) {
  if (cell.isDisposed || reason.message.startsWith('Canceled')) {
    ran = false;
  } else {
    onCellExecuted({
      cell,
      success: false,
      error: reason
    });
    throw reason;
  }
}

if (ran) {
  onCellExecuted({ cell, success: true });
}

This is not the case with jupyter-server-nbmodel which omits the error information:

jupyter-server-nbmodel/src/executor.ts

Lines 130 to 144 in 0a6c683

	const data = await response.json();
	success = data['status'] === 'ok';
	} catch (error: unknown) {
	onCellExecuted({
	cell,
	success: false
	});
	if (cell.isDisposed) {
	return false;
	} else {
	throw error;
	}
	}
	onCellExecuted({ cell, success });