[IMP] stock_picking_batch_custom: show product code as separate optional column

Add product_default_code related field to stock.move.line and
stock.picking.batch.summary.line. Show it as a hidden-by-default column
to the right of product_id in both detailed operations and product summary
views. Hide the code prefix from the product name via display_default_code
context so sorting is alphabetical.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

stock_picking_batch_custom/models/stock_move_line.py

@@ -17,6 +17,12 @@ class StockMoveLine(models.Model):
         readonly=True,
     )
 
+    product_default_code = fields.Char(
+        string="Product Code",
+        related="product_id.default_code",
+        readonly=True,
+    )
+
     is_collected = fields.Boolean(
         string="Collected",
         default=False,

stock_picking_batch_custom/models/stock_picking_batch.py

@@ -253,6 +253,11 @@ class StockPickingBatchSummaryLine(models.Model):
         store=True,
         readonly=True,
     )
+    product_default_code = fields.Char(
+        string="Product Code",
+        related="product_id.default_code",
+        readonly=True,
+    )
     product_uom_id = fields.Many2one(
         comodel_name="uom.uom",
         string="Unit of Measure",

stock_picking_batch_custom/views/stock_picking_batch_views.xml

@@ -5,10 +5,9 @@
         <field name="model">stock.picking.batch.summary.line</field>
         <field name="arch" type="xml">
             <list create="0" delete="0" default_order="product_categ_id,product_id">
-                <!-- Mostrar categoría a la izquierda del producto para mejor legibilidad -->
                 <field name="product_categ_id" readonly="1"/>
-                <field name="product_id" readonly="1"/>
+                <field name="product_id" readonly="1" context="{'display_default_code': False}"/>
-                <!-- Unidad de medida opcional (oculta por defecto si el usuario lo decide) -->
+                <field name="product_default_code" readonly="1" optional="hide"/>
                 <field name="product_uom_id" readonly="1" optional="hide"/>
                 <field name="qty_demanded" readonly="1"/>
                 <field name="qty_done" readonly="1"/>
@@ -50,6 +49,12 @@
             <xpath expr="//field[@name='product_id']" position="before">
                 <field name="product_categ_id" readonly="1"/>
             </xpath>
+            <xpath expr="//field[@name='product_id']" position="attributes">
+                <attribute name="context">{'display_default_code': False}</attribute>
+            </xpath>
+            <xpath expr="//field[@name='product_id']" position="after">
+                <field name="product_default_code" readonly="1" optional="hide"/>
+            </xpath>
             <xpath expr="//field[@name='product_uom_id']" position="attributes">
                 <attribute name="optional">hide</attribute>
             </xpath>