add helpful exception if unable to set attribute

Author: kbond

src/TwigComponent/src/HasAttributesTrait.php

@@ -36,6 +36,12 @@ public function mountAttributes(array $data): array
             $data = array_merge($this->attributes->all(), $data);
         }
 
+        foreach ($data as $key => $value) {
+            if (!is_scalar($value)) {
+                throw new \LogicException(sprintf('Unable to use "%s" (%s) as an attribute. Attributes must be scalar. If you meant to mount this value on your component, make sure this is a writable property.', $key, get_debug_type($value)));
+            }
+        }
+
         $this->attributes = new ComponentAttributes($data);
 
         return [];