[FIX] product_sale_price_from_pricelist: Properly handle template vs variant IDs

Instead of converting templates to variants before calling super(), check
the model type when processing results. If working with product.template,
get the variant from the template using browse(). This preserves the
expected ID mapping in the result dictionary and avoids lambda variable
binding issues.

Fixes: KeyError: 9 in pricelist computation

product_sale_price_from_pricelist/models/product_pricelist.py

@@ -16,15 +16,6 @@ class ProductPricelist(models.Model):
         ProductPricelistItem = self.env["product.pricelist.item"]
         ProductProduct = self.env["product.product"]
 
-        # Ensure we're working with product.product, not product.template
-        if products and products._name == "product.template":
-            # Convert templates to their variants
-            _logger.info(
-                "[PRICELIST DEBUG] Converting product.template to product.product: %s",
-                products.ids,
-            )
-            products = products.mapped("product_variant_ids")
-
         _logger.info(
             "[PRICELIST DEBUG] _compute_price_rule called with products=%s (model=%s), quantity=%s",
             products.ids,
@@ -55,7 +46,22 @@ class ProductPricelist(models.Model):
                     item_id,
                 )
                 if item.base == "last_purchase_price":
+                    # product_id could be from product.template or product.product
+                    # Check which model we're working with
+                    if products._name == "product.template":
+                        # Get the variant from the template
+                        template = products.browse(product_id)
+                        if template.exists():
+                            product = template.product_variant_id
+                        else:
+                            _logger.warning(
+                                "[PRICELIST] Template ID %s not found in products",
+                                product_id,
+                            )
+                            continue
+                    else:
                         product = ProductProduct.browse(product_id)
+
                     price = product.last_purchase_price_received
                     _logger.info(
                         "[PRICELIST DEBUG] Product %s: last_purchase_price_received=%s, item.price_discount=%s",