wip: guest account registration (self-service and booking create flow)

tests/Support/TestPublicFormRateLimiter.php

@@ -28,6 +28,11 @@ class TestPublicFormRateLimiter extends PublicFormRateLimiter
         return $this->consume($email, $request);
     }
 
+    public function isPortalAccessAllowed(string $email, Request $request): bool
+    {
+        return $this->consume($email, $request);
+    }
+
     public function createBucketKey(string $email, ?string $clientIp): string
     {
         return hash('sha256', mb_strtolower(trim($email)).'|'.($clientIp ?? 'unknown'));