Manually override VAT on Invoices

When Fresh calculates VAT on Proforma Invoices, users must be able to manually adjust the VAT amount on Fresh if the system rounding is incorrect.

Currently, the VAT amount appears correct on the Draft Proforma Invoice, but in some cases, when the document is converted to a Tax Invoice, the VAT amount changes due to rounding differences. This discrepancy results in incorrect invoicing and leads to the need for credit notes, creating unnecessary rework.