Earlier quoted context omitted.
Having been in a similar situation, my sympathies; I've found it to be a very strange sensation. The burnt-out knows exactly what work tasks they need to do, they know that it's easily within their own capabilities, and they (at a conscious level at least) even desperately want to do the tasks to fulfill their professional obligations (or to simply continue getting paid). But the body just will not do it or forcing i…
OMG you've nailed exactly what I've been feeling for the past six months or so. :/
I've never personally experienced true burnout, but I also have a policy of taking it seriously and making sure that I do something about it long before it becomes a permanent trauma, and I have had to call a couple of multi-week vacations with relatively short notice, or perhaps announce a vacation a month before the end of some important project. Sometimes it's even as simple as waking up on Friday and just realizing that today is a "Nope!" and taking it off. I think if you nip it in the bud you often may not even need to do it that often. But take it seriously.
And if your job won't let you do that, take seriously the possibility of finding a new one. Yeah, finding a new job sucks, but permanently burning out sucks way more.