Dues invoicing fix
- Fixed: membership invoices are now issued for the correct annual dues. A defect in how the dues line item was attached to the Stripe invoice could produce an invoice showing $0; new joins and renewals now verify the invoice amount with Stripe before it is issued, and refuse to send one that does not match the published dues for that tier.
- Anyone who received a $0 invoice is being reissued a correct one directly.