[IMP] stock: product category for inventory Lines

Add `categ_id` field (related of `product_id`) in `stock.inventory.line`
model to able user to filter and group by product category.

Task #2026952

closes odoo/odoo#34349

Signed-off-by: Simon Lejeune (sle) <sle@openerp.com>

addons/stock/models/stock_inventory.py

@@ -287,6 +287,7 @@ class InventoryLine(models.Model):
     product_qty = fields.Float(
         'Counted Quantity',
         digits=dp.get_precision('Product Unit of Measure'), default=0)
+    categ_id = fields.Many2one(related='product_id.categ_id', store=True)
     location_id = fields.Many2one(
         'stock.location', 'Location',
         domain=lambda self: self._domain_location_id(),

addons/stock/views/stock_inventory_views.xml

@@ -79,6 +79,8 @@
                 <group  expand='0' string='Group by...'>
                    <filter string='Location' name="location" domain="[]" context="{'group_by' : 'location_id'}"/>
                    <filter string='Packaging' name="packaging" domain="[]" context="{'group_by' : 'package_id'}"/>
+                   <filter string='Product' name="product" domain="[]" context="{'group_by' : 'product_id'}"/>
+                   <filter string='Product Category' name="product_category" domain="[]" context="{'group_by' : 'categ_id'}"/>
                 </group>
             </search>
         </field>