Generate an invoice ONLY after payment has been confirmed#4855

Provide a way to generate invoices ONLY when I manually request them. I mean, for ON-SITE payment types, it makes more sense to generate the invoice only when I mark the transaction as PAID. If I have cancellations, for example, I will have an unnecessary numbering gap.

Imagine a scenario where a client books on 30/03 but comes to me and pays on-site on 05/09. The invoice will show 30/03 rather than 05/09. Legally, this creates inconsistencies for both the client and my company.

If the invoice is created only after payment confirmation, both the issue date and the numbering will consider the payment date rather than the booking date.

Ps: Otherwise, it would be useful to be able to change the invoice number manually at any time (the simplest way to work around the previous problem).