[IMP] scrap_reason_code: define product categories allowed for each code

Also redefine reason code form view a bit.

scrap_reason_code/models/reason_code.py

@@ -1,5 +1,6 @@
 # Copyright (C) 2019 IBM Corp.
 # Copyright (C) 2019 Open Source Integrators
+# Copyright 2023 ForgeFlow S.L. (https://www.forgeflow.com)
 # License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl).
 
 from odoo import fields, models
@@ -16,3 +17,10 @@ class ScrapReasonCode(models.Model):
         string="Scrap Location",
         domain="[('scrap_location', '=', True)]",
     )
+    product_category_ids = fields.Many2many(
+        string="Allowed Product Categories",
+        comodel_name="product.category",
+        help="Indicate the cateogories of products that can use this reason code "
+        "when doing a scrap. If left empy, this reason code can be used "
+        "with any product.",
+    )