Add v3 method to SubscriptionPurchaseController

app/Http/Controllers/ClientPortal/SubscriptionPurchaseController.php

@@ -71,6 +71,17 @@ class SubscriptionPurchaseController extends Controller
         ]);
     }
 
+    public function v3(Subscription $subscription, Request $request)
+    {
+        // Todo: Prerequirement checks for subscription.
+
+        return view('billing-portal.v3.index', [
+            'subscription' => $subscription,
+            'hash' => Str::uuid()->toString(),
+            'request_data' => $request->all(),
+        ]);
+    }
+
     /**
      * Set locale for incoming request.
      *