4.30.0
(feat): XML (TwiML) builders can now carry XML comments. comment(text) adds <!--text--> inside the element at
its position in the ordered content (interleaved with addText segments and child elements), while
commentBefore(text) / commentAfter(text) render a comment immediately before or after the element
itself (as a sibling in its parent, or around the root element after the XML declaration). Comments in
parsed documents are preserved by fromXml and round-trip through toXml; XmlNode.comment(...)
exposes the same for untyped elements.