Introduced a new JS script block in download.php which gets triggered when user session is not
valid or on missing parameters invoice or type.
Dialog.js has been modified to change how invoices are downloaded. Instead of creating an
invisible iframe, now it leverages fetch API and download.js to get the invoice and proceed
downloading.
Corrected indentation of the text and button image in the dialog box of the invoice download.
Invoice.php updated to include a new check for net value invoices. Adds articles to the
ZugferdDocumentBuilder and calculates VAT based on the detected invoice type (net or gross). This
ensures accurate electronic invoices.
