[FIX] pos: reconciliation and performance issues (#24610)

Before this commit, the complete list of orders of the pos session
was processed through the reconciliation mechanism to check if an
automatic reconciliation was possible (introduced in a controversial
'bug fix' at fe70f07, itself a backport of a master commit at
a2319b4). The goal of this auto-reconciliation was to avoid potentially
silent and numerous customer statements that could be reconciled
automatically.

This is mostly useless in a lot of cases, since a lot of users do not
set any partner_id value on the pos order - there is nothing useful to
reconcile. Going through the whole list of orders is time-wasting
(especially since the reconciliation method does not scale well).

Combine this with users who do not close their POS session often enough
and closing a session can suddenly take up to several hours to process
instead of several seconds with practically no obvious gain.

After this commit, only orders which have a partner set on them will be
auto-reconciled.

opw-1818838 and opw-1817172

addons/point_of_sale/models/pos_session.py

@@ -29,8 +29,8 @@ class PosSession(models.Model):
                 if order.state not in ('paid'):
                     raise UserError(_("You cannot confirm all orders of this session, because they have not the 'paid' status"))
                 order.action_pos_order_done()
-            orders = session.order_ids.filtered(lambda order: order.state in ['invoiced', 'done'])
-            orders.sudo()._reconcile_payments()
+            orders_to_reconcile = session.order_ids.filtered(lambda order: order.state in ['invoiced', 'done'] and order.partner_id)
+            orders_to_reconcile.sudo()._reconcile_payments()
 
     config_id = fields.Many2one(
         'pos.config', string='Point of Sale',