fix: Calculate gross amount using price_subtotal instead of price_subtotal_incl for order lines.

models/pos_session.py

@@ -42,9 +42,9 @@ class PosSession(models.Model):
                 
                 # We can sum the positive lines to get the "Sale Value".
                 gross_amount = sum(
-                    line.price_subtotal_incl 
+                    line.price_subtotal 
                     for line in order.lines 
-                    if line.price_subtotal_incl > 0
+                    if line.price_subtotal > 0
                 )
                 
                 if float_is_zero(gross_amount, precision_rounding=self.currency_id.rounding):