Gate payment gateway behind Pro and Business plans.

Free accounts can no longer connect or use Paystack/Flutterwave/Hubtel;
settings show an upgrade path and checkout requires a paid subscription.

app/Http/Controllers/Qr/AccountController.php

@@ -6,6 +6,7 @@ use App\Http\Controllers\Controller;
 use App\Models\PaymentGatewaySetting;
 use App\Models\QrSetting;
 use App\Services\Billing\BillingClient;
+use App\Services\Events\SubscriptionService;
 use App\Services\Payments\MerchantGatewayService;
 use App\Support\AccountBranding;
 use App\Support\Qr\QrCornerStyleCatalog;
@@ -21,6 +22,7 @@ class AccountController extends Controller
     public function __construct(
         private BillingClient $billing,
         private MerchantGatewayService $gateway,
+        private SubscriptionService $subscriptions,
     ) {}
 
     private function topupUrl(): string
@@ -83,6 +85,7 @@ class AccountController extends Controller
             'cornerInnerStyles' => QrCornerStyleCatalog::innerStyles(),
             'frameStyles' => QrFrameStyleCatalog::visible(),
             'gateway' => $this->gateway->settingFor($account),
+            'canUsePaymentGateway' => $this->subscriptions->canUsePaymentGateway($account),
         ]);
     }
 
@@ -164,7 +167,7 @@ class AccountController extends Controller
         );
 
         $provider = (string) ($data['gateway_provider'] ?? '');
-        if ($provider !== '') {
+        if ($provider !== '' && $this->subscriptions->canUsePaymentGateway($account)) {
             $existing = PaymentGatewaySetting::query()->firstOrNew([
                 'owner_ref' => $account->public_id,
             ]);