[IMP] mrp_multi_level: enchance traceability with origin.

* keept description of planned orders verbose.
* make it translatable in most cases.
* while grouping demand include the product in the description.
* add `origin` field not mrp moves and planned orders. Fill it
  with top level demand origin.

mrp_multi_level/models/mrp_move.py

@@ -63,6 +63,7 @@ class MrpMove(models.Model):
         selection=[("s", "Supply"), ("d", "Demand")], string="Type"
     )
     name = fields.Char(string="Description")
+    origin = fields.Char(string="Source Document")
     parent_product_id = fields.Many2one(
         comodel_name="product.product", string="Parent Product", index=True
     )

mrp_multi_level/models/mrp_planned_order.py

@@ -12,6 +12,7 @@ class MrpPlannedOrder(models.Model):
     _order = "due_date, id"
 
     name = fields.Char(string="Description")
+    origin = fields.Char(string="Source Document")
     product_mrp_area_id = fields.Many2one(
         comodel_name="product.mrp.area",
         string="Product MRP Area",