Adds invoice voiding (cancellation) with a charge policy.
New:
- Meteric::voidInvoice($invoice, VoidCharges) cancels an unpaid invoice issued in error. It refuses an invoice with a payment (use a credit note to reverse a paid one). Voiding routes through the driver, so the lexoffice driver voids an unsent draft and refuses a finalized document.
- VoidCharges decides the charges' fate: Keep (default, leave them for a manual re-issue such as a wrong address), Release (return to pending to bill again on the next run), or Discard (void the charges too).
Requires PHP 8.3+, Laravel 12, PostgreSQL.