Insert wikitext from AI response

[simontaurus]

This requires a transformation of wikitext to ve model (see: https://www.mediawiki.org/wiki/Talk:VisualEditor/Gadgets#Working_with_the_underlying_wikitext) here:

mediawiki-extensions-AIEditingAssistant/resources/ui/Inspector.js

Line 43 in 1d309b8

fragment.insertContent( newText );