Credit students for cancelled paid lessons

Cancelling a lesson that was already paid for now credits the student that money instead of leaving it as a manual refund, and the daily scheduled-billing scan applies any available credit against their due charges before emailing the notice. - New us_credits ledger + us_payments.credit_applied column (Payment::netDue). - PaymentService::creditForCancelledLesson issues a per-lesson share of the covering payment's total; wired into all three cancel paths (student self-cancel, instructor status update, admin student-detail cancel). - PaymentService::applyCredits draws credit down FIFO across a run's charges, marking a fully-covered charge paid-by-credit; the notice shows the credit applied and reduced total, and the admin queue shows net due. - Student detail page shows a student's credit balance and history. Ships as part of the unreleased 1.2.0 (same release as scheduled billing). Tests: composer test (585), composer lint, composer cs all pass. Co-Authored-By: Claude Opus 4.8 <[email protected]>
2026-07-24 15:32:20 -03:00
parent 3f9aef7746
commit e8e66eef3c
30 changed files with 1210 additions and 80 deletions
@@ -69,8 +69,12 @@ at-registration payments have no batch and appear on their own.
 ## Cancellation
 Scheduled payments are never auto-voided. `PaymentService::voidPending` acts only on
 legacy at-registration payments (`! Payment::isScheduled()`), so cancelling one lesson
-never voids a shared monthly charge, never refunds, and never rebills. Refunds/credits
-are a manual, admin-side decision.
+never voids a shared monthly charge, never refunds, and never rebills.
+
+Cancelling a lesson that was **already paid** credits the student one lesson's share
+of what they paid (`PaymentService::creditForCancelledLesson`), and the next scan
+applies that credit against their due charges before emailing the notice
+(`PaymentService::applyCredits`). See `credits.md` for the full model.

 ## Implementation
 - Runner: `Unsupervised\Schedular\Payment\ScheduledBillingRunner`