feat(ECR-014): MembershipPlan 套餐配置并 Closed

membership_plans 表、admin 套餐页、Grant/CreateOrder 读表；
Loop continuous 自动 Approve/Closed。Next：ECR-015 RedemptionCode。

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

apps/api/migrations/000017_membership_plans.down.sql

@@ -0,0 +1,3 @@
+DELETE FROM admin_role_permissions
+WHERE code IN ('admin.membership.plans.read', 'admin.membership.plans.write');
+DROP TABLE IF EXISTS membership_plans;