feat(ECR-015): RedemptionCode 兑换码并 Closed

批次生成/作废、C 端兑码延长会员；admin-h5 /codes。
Loop continuous。Next：ECR-016 UserIntelligence。

Co-authored-by: Cursor <cursoragent@cursor.com>

apps/api/migrations/000018_redemption_codes.down.sql

@@ -0,0 +1,4 @@
+DELETE FROM admin_role_permissions
+WHERE code IN ('admin.membership.codes.read', 'admin.membership.codes.write');
+DROP TABLE IF EXISTS redemption_codes;
+DROP TABLE IF EXISTS redemption_batches;