Pre-/appending additional text when using INSERT_TEXT in Maven Plugin "xwiki-commons-tool-xar-plugin"

Assume you are using Maven plugin "xwiki-commons-tool-xar-plugin" for adding the content of a groovy file to an XWiki xml file.
Using transformation action INSERT_TEXT is doing a good job here.
But now assume that you want that inserted groovy action be prepended with {{groovy wiki="false"}} and appended with {{/groovy}}.
I think this is currently not possible- you have to add that lines to the goovy file itself, but then it's no real groovy file any longer.
Would be great if we could add two parameters to the INSERT_TEXT action to allow this - or whatever idea you have to solve that issue?
Thank you very much in advance.