На воре шапка горит （the hat the thief is wearing is on fire...) 火炎焱。。。。义

This ends with Putin dead or in the docket for war crimes. 

Russia, supposedly, is willing to make concessions to Ukraine in exchange for a ceasefire.

Too bad literally the entire world INCLUDING XI JINPING have figured out that Russia (Putin) lies constantly and cannot be trusted. As the Chinese government increasingly figures out the Putin regime are war criminals and Russia is now a pariah state we can fully expect China AND Germany to position themselves to try to pick up the pieces. Germany will try to gain access to Russian hydrocarbons, so will China. China will try to make former Soviet central asian states (all of them) into Clients of Beijing. Caucasian states, most notably Georgia, will inevitably draw closer to the EU and NATO.

Even if Putin were not a literal war criminal, a compulsive liar, cognitive biases also explain why no one will compromise or negotiate any truce. The "sunk cost fallacy" is the idea that people will "throw good money after bad" and just about always "double down". Thus Putin himself likely could not negotiate a truce, even if he were entirely honest and in good faith, which of course he isn't.  Escalation of commitment likewise dooms this to greater conflict rather than a rational negotiated "solution": who negotiates with war criminals, rapists, robbers, mass murderers? Even if they were honest no one would ever negotiate with such.

 So the conflict will drag on until the Russian army collapses OR Putin resigns, which he will never do, OR until Putin is "removed" from office: likely Permanently.

It's a race between the unsupplied demoralized Russian victims of Putin's propaganda surrender en mass versus Putin's partners in crime deciding to seize power from him at gunpoint. I doubt he will survive. Oh, and the people worrying about nuclear war? Like anyone would obey him were he to order nuclear release, Putin himself admits having survived about a half dozen assassination attempts.

Let's hope Putin tenders his resignation: spoiler -- he won't. Nor will Ukraine surrender.

Ukraine will win, and then Putin and his partners in crime will find themselves in the docket for war crimes: well, the survivors anyway. Purge and counter-purge dooms the Russian regime to collapse, even if its army were other than an incompetent horde of murderous rapist looters.