You might be able to accomplish something like this by Javascript, like I did here:
https://forum.dokuwiki.org/d/21535-bureaucracy-and-pagemod-problem-with-line-breaks
But this only works, if you paste your text via an input form, here created by use of the bureaucracy plugin and the pagemod plugin.
As a quick test I just copy&pasted your post above into my setup input form on my testpage and voila, it comes out on my testpage exactly as here in the forum post with all the linebreaks and newlines. (I never tried copy/paste with my input form before.)
It might also work when using one of the WYSIWYG editors, like: https://www.dokuwiki.org/plugin:ckgedit (but I don't know).