[IMP] website_sale_aplicoop: propagate consumer_group_id directly from group_order

- Add consumer_group_id to sale.order for tracking the consumer group
- Fix stock.picking consumer_group_id to use sale_id.consumer_group_id
- Add group_ids inverse relation in res.partner for bidirectional access
- Remove auto-calculation of consumer_group_id, data comes directly from group_order.group_ids[0]
- Add debug logging for consumer_group propagation
- commitment_date propagates directly from group_order (no recalculation)

website_sale_aplicoop/models/sale_order_extension.py

@@ -22,7 +22,7 @@ class SaleOrder(models.Model):
 
     pickup_day = fields.Selection(
         selection=_get_pickup_day_selection,
-        help="Day of week when this order will be picked up (inherited from group order)",
+        help="Day of week when this order will be picked up",
     )
 
     group_order_id = fields.Many2one(
@@ -30,13 +30,19 @@ class SaleOrder(models.Model):
         help="Reference to the consumer group order that originated this sale order",
     )
 
+    consumer_group_id = fields.Many2one(
+        "res.partner",
+        domain="[('is_group', '=', True)]",
+        help="Consumer group for this order",
+    )
+
     pickup_date = fields.Date(
-        help="Calculated pickup/delivery date (inherited from consumer group order)",
+        help="Pickup/delivery date",
     )
 
     home_delivery = fields.Boolean(
         default=False,
-        help="Whether this order includes home delivery (inherited from consumer group order)",
+        help="Whether this order includes home delivery",
     )
 
     def _get_name_portal_content_view(self):