{"content":"[assist-base-service dev journal] feat-paypal-recharge (commit 380ee3a): schema groundwork for the PayPal recharge gateway. tb_traffic_recharge_order gains gatewayOrderId (PayPal order id, UNIQUE, NULL until known) so CHECKOUT.ORDER.APPROVED events can be reconciled and captured. Fixed a latent blocker: gatewayTxnId was DEFAULT '' NOT NULL under a UNIQUE index, so the second unpaid order fleet-wide would collide on '' — normalized to NULL-until-paid (unique indexes ignore NULLs, preserving exactly-once capture). Idempotent migration appended to sql/update.sql; GORM default:null tags verified via DryRun test (fields omitted from INSERT when empty).","contentType":"text/plain;utf-8","attachments":[],"quotePin":""}