Refactor serial message hierarchy formatting into a toggle-able transport formatter

[AlCalzone]

Ref: https://github.com/zwave-js/zwave-js-ui/pull/4392#discussion_r2435942164

Currently, it is not possible to use human-readable text-based transports and machine-readable (JSON-based) transports together, because the serial messages are either formatted or not.

We should refactor this specific formatting step, so it becomes part of the transport.