[IMP] stock: usability improvement

Description of the issue/feature this PR addresses:
- Task : https://www.odoo.com/web#id=1891230&action=333&active_id=131&model=project.task&view_type=form&menu_id=4720
- Pad : https://pad.odoo.com/p/r.c685147bff2284699d1933fb36e3fec3

Current behavior before PR:
- Usability MTO route

Desired behavior after PR is merged:
- Rename stock_location_route "Make to Order (MTO)" into "Replenish on Order (MTO)".
- The field responsible on the product should be empty by default and it shouldn't be required.
  If empty, the next activity should be assigned to the "system" (the admin)

--
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closes odoo/odoo#27554

addons/product_expiry/models/production_lot.py

@@ -1,7 +1,7 @@
 # -*- coding: utf-8 -*-
 # Part of Odoo. See LICENSE file for full copyright and licensing details.
 import datetime
-from odoo import api, fields, models, _
+from odoo import api, fields, models, SUPERUSER_ID, _
 
 
 class StockProductionLot(models.Model):
@@ -81,7 +81,7 @@ class StockProductionLot(models.Model):
                 ('mail_activity_type_id','=', mail_activity_type)]))
         for lot in lots:
             lot.activity_schedule('product_expiry.mail_activity_type_alert_date_reached',
-            user_id=lot.product_id.responsible_id.id, note=_("The alert date has been reached for this lot/serial number")
+            user_id=lot.product_id.responsible_id.id or SUPERUSER_ID, note=_("The alert date has been reached for this lot/serial number")
         )
 
 class ProcurementGroup(models.Model):

addons/stock/data/stock_data.xml

@@ -66,7 +66,7 @@
         
         <!-- set a lower sequence on the mto route than on the resupply routes -->
         <record id="route_warehouse0_mto" model='stock.location.route'>
-            <field name="name">Make To Order</field>
+            <field name="name">Replenish on Order (MTO)</field>
             <field name="company_id"></field>
             <field name="sequence">5</field>
         </record>

addons/stock/models/product.py

@@ -402,7 +402,7 @@ class ProductTemplate(models.Model):
     _inherit = 'product.template'
 
     responsible_id = fields.Many2one(
-        'res.users', string='Responsible', default=lambda self: self.env.uid, required=True,
+        'res.users', string='Responsible',
         help="This user will be responsible of the next activities related to logistic operations for this product.")
     type = fields.Selection(selection_add=[('product', 'Storable Product')])
     property_stock_production = fields.Many2one(
@@ -443,7 +443,7 @@ class ProductTemplate(models.Model):
     route_ids = fields.Many2many(
         'stock.location.route', 'stock_route_product', 'product_id', 'route_id', 'Routes',
         domain=[('product_selectable', '=', True)],
-        help="Depending on the modules installed, this will allow you to define the route of the product: whether it will be bought, manufactured, MTO, etc.")
+        help="Depending on the modules installed, this will allow you to define the route of the product: whether it will be bought, manufactured, replenished on order, etc.")
     nbr_reordering_rules = fields.Integer('Reordering Rules', compute='_compute_nbr_reordering_rules')
     # TDE FIXME: really used ?
     reordering_min_qty = fields.Float(compute='_compute_nbr_reordering_rules')

addons/stock/models/stock_rule.py

@@ -7,7 +7,7 @@ from dateutil.relativedelta import relativedelta
 from odoo.tools.misc import split_every
 from psycopg2 import OperationalError
 
-from odoo import api, fields, models, registry, _
+from odoo import api, fields, models, registry, SUPERUSER_ID, _
 from odoo.osv import expression
 from odoo.tools import DEFAULT_SERVER_DATETIME_FORMAT, float_compare, float_round
 
@@ -245,7 +245,7 @@ class StockRule(models.Model):
             self.env['mail.activity'].create({
                 'activity_type_id': activity_type_id,
                 'note': note,
-                'user_id': product_id.responsible_id.id,
+                'user_id': product_id.responsible_id.id or SUPERUSER_ID,
                 'res_id': product_id.product_tmpl_id.id,
                 'res_model_id': self.env.ref('product.model_product_template').id,
             })

odoo/addons/test_main_flows/static/src/js/tour.js

@@ -58,8 +58,8 @@ tour.register('main_flow_tour', {
     content: _t('Uncheck Buy'),
     position: 'right',
 }, {
-    trigger: '.o_field_widget[name=route_ids] .custom-checkbox > label:contains("Make To Order")',
-    content: _t('Uncheck  Make To Order'),
+    trigger: '.o_field_widget[name=route_ids] .custom-checkbox > label:contains("Replenish on Order (MTO)")',
+    content: _t('Uncheck  Replenish on Order (MTO)'),
     position: 'right',
 }, {
     trigger: '.o_notebook a:contains("General Information")',
@@ -114,8 +114,8 @@ tour.register('main_flow_tour', {
     content: _t('Go to inventory tab'),
     position: 'top',
 }, {
-    trigger: '.o_field_widget[name=route_ids] .custom-checkbox > label:contains("Make To Order")',
-    content: _t('Check Make To Order'),
+    trigger: '.o_field_widget[name=route_ids] .custom-checkbox > label:contains("Replenish on Order (MTO)")',
+    content: _t('Check Replenish on Order (MTO)'),
     position: 'right',
 }, {
     trigger: '.o_notebook a:contains("Purchase")',