Référence existante utilisée : WC-REFUND-TEST-EXISTANT
A  CreditNote coupure NULL       date 2026-09-01 ref NULL                     => créé #446 type 2  OK
B  CreditNote coupure '2026-09-13' date 2026-09-12 ref 'WC-REFUND-99999901'     => refusé  OK
      [Splash Client] Credit note dated 2026-09-12 is before 2026-09-13: refused, earlier refunds are booked by hand.
C  CreditNote coupure '2026-09-13' date 2026-09-13 ref NULL                     => refusé  OK
      [Splash Client] Credit note without external reference: refused, a duplicate could not be detected.
D  CreditNote coupure '2026-09-13' date 2026-09-13 ref 'WC-REFUND-TEST-EXISTANT' => refusé  OK
      [Splash Client] External reference WC-REFUND-TEST-EXISTANT is already used by FA2608-0271: credit note refused.
E  CreditNote coupure '2026-09-13' date 2026-09-13 ref 'WC-REFUND-99999902'     => créé #447 type 2  OK
F  CreditNote coupure '13/09/2026' date 2026-09-13 ref 'WC-REFUND-99999903'     => refusé  OK
      [Splash Client] SPLASH_CREDIT_NOTE_MIN_DATE is not a Y-m-d date: credit note creation refused.
G  Invoice    coupure '2026-09-13' date 2026-09-01 ref NULL                     => créé #448 type 0  OK
Transaction annulée.
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