**Notable feature changes**
- PoS app continues to load even if no nomenclature_id is configured.
- When scanning, an error popup is shown to the user mentioning about
the misconfiguration.
- We introduce a default error handler that shows the ErrorBarcodePopup
when there are no registered barcode handlers via the
`useBarcodeReader` hook.
closes odoo/odoo#115906
Related: odoo/enterprise#38444
Signed-off-by: Samuel Degueldre <sad@odoo.com>