[FIX] point_of_sale: fix raceback when deleting orderline

Steps to reproduce:
- Activate customer display.
- Open a pos session.
- Open the customer display.
- Add orderline.
- Delete the orderline. Then there's traceback.

This is caused by the fact that the `effect` used to update the customer
display is synchronous, and when removing an order, `splice` is applied
in multiple steps, and causes multiple notifications to the underlying
reactive. At some of those steps, the reactive state is inconsistent
(ie, one of the slots of the reactive array is empty) causing the call
to map to result in an array with empty slots which cannot be used in
`Object.fromEntries`.

This commit fixes that my batching the updates to the customer display
in the next microtask tick, meaning that the update will never be done
with an inconsistent state.

closes odoo/odoo#118743

Signed-off-by: Samuel Degueldre <sad@odoo.com>

addons/point_of_sale/static/src/app/customer_display_service.js

@@ -1,5 +1,6 @@
 /** @odoo-module */
 
+import { batched } from "@point_of_sale/js/utils";
 import { effect, Reactive } from "@point_of_sale/utils";
 import { registry } from "@web/core/registry";
 import { pick } from "@web/core/utils/objects";
@@ -136,7 +137,10 @@ export const customerDisplayService = {
             // of having it be a part of the chrome and having to propagate complexity everywhere.
             env.services.customer_display = display;
             // Register an effect to update the display automatically when anything it renders changes
-            effect((display) => display.update(), [display]);
+            effect(
+                batched((display) => display.update()),
+                [display]
+            );
         });
 
         return service;