[IMP] point_of_sale: Allow to filter partners based on pos orders

Especially used for e-marketing to filter the customers who purchased from store using pos.

Related Task ID: 1931528

closes odoo/odoo#30645

addons/point_of_sale/models/res_partner.py

@@ -11,6 +11,7 @@ class ResPartner(models.Model):
         help="The number of point of sales orders related to this customer",
         groups="point_of_sale.group_pos_user",
     )
+    pos_order_ids = fields.One2many('pos.order', 'partner_id', readonly=True)
     barcode = fields.Char(oldname='ean13', help="Use a barcode to identify this contact from the Point of Sale.", copy=False)
 
     _sql_constraints = [

addons/point_of_sale/views/res_partner_view.xml

@@ -12,7 +12,7 @@
                         context="{'search_default_partner_id': active_id,'default_partner_id': active_id}"
                         attrs="{'invisible': ['|', ('customer', '=', False), ('pos_order_count', '=', 0)]}"
                         icon="fa-shopping-bag">
-                        <field string="POS Sales" name="pos_order_count" widget="statinfo"/>
+                        <field string="PoS Orders" name="pos_order_count" widget="statinfo"/>
                     </button>
                 </button>
                 <xpath expr="//group[@name='purchase']" position="after">