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/internal/repository/report_repo.go

@@ -316,6 +316,38 @@ func AskPackAmountCents(plan string) int {
 	}
 }
 
+// MembershipPlanAmountCents returns catalog price or fallback for membership plans.
+func (r *ReportRepo) MembershipPlanAmountCents(ctx context.Context, plan string) (int, error) {
+	var amount int
+	var active bool
+	err := r.Pool.QueryRow(ctx, `
+		SELECT amount_cents, active FROM membership_plans WHERE code=$1`, plan,
+	).Scan(&amount, &active)
+	if errors.Is(err, pgx.ErrNoRows) {
+		return membershipAmountFallback(plan), nil
+	}
+	if err != nil {
+		return 0, err
+	}
+	if !active {
+		return 0, errString("plan inactive")
+	}
+	return amount, nil
+}
+
+func membershipAmountFallback(plan string) int {
+	switch plan {
+	case "month":
+		return 2500
+	case "quarter":
+		return 6800
+	case "year":
+		return 19800
+	default:
+		return 2500
+	}
+}
+
 var errMissingReport = errString("report_id required for deep_access")
 
 type errString string