unify access to custom fields (#3106)

src/Entity/Timesheet.php

@@ -719,6 +719,20 @@ class Timesheet implements EntityWithMetaFields, ExportItemInterface
         return null;
     }
 
+    /**
+     * @param string $name
+     * @return bool|int|string|null
+     */
+    public function getMetaFieldValue(string $name)
+    {
+        $field = $this->getMetaField($name);
+        if ($field === null) {
+            return null;
+        }
+
+        return $field->getValue();
+    }
+
     public function setMetaField(MetaTableTypeInterface $meta): EntityWithMetaFields
     {
         if (null === ($current = $this->getMetaField($meta->getName()))) {