feat: Invoice View, payment Daten, Datenbankstruktur aufgeräumt

ajax/invoices/temporary/html.php

bin/backend/controls/panels/TemporaryInvoice.Data.html

bin/backend/controls/panels/TemporaryInvoice.js

database.xml

locale.xml

src/QUI/ERP/Accounting/Invoice/Handler.php

src/QUI/ERP/Accounting/Invoice/Invoice.php

src/QUI/ERP/Accounting/Invoice/InvoiceView.php

src/QUI/ERP/Accounting/Invoice/TemporaryInvoice.php