feat: implement tenant OAuth flow and guest achievements

app/Http/Middleware/TenantIsolation.php

@@ -27,8 +27,12 @@ class TenantIsolation
         }
 
         // Set tenant context for query scoping
-        DB::statement("SET @tenant_id = ?", [$tenantId]);
-        
+        $connection = DB::connection();
+        if (in_array($connection->getDriverName(), ['mysql', 'mariadb'])) {
+            $connection->statement('SET @tenant_id = ?', [$tenantId]);
+        }
+
+
         // Add tenant context to request for easy access in controllers
         $request->attributes->set('current_tenant_id', $tenantId);
 
@@ -58,4 +62,4 @@ class TenantIsolation
         // 4. For tenant-specific resources, use token tenant_id
         return null;
     }
-}
+}