What's the Deal With the Mysterious Drone Attack on Putin?

So, who fired two drones at the Kremlin in the wee hours of Wednesday morning, and what does the act say about the course of the war in Ukraine? The whole business is a mystery, and may remain so forever, except to those who did the deed. The two questions are, of course, related; the intended impact on the war depends on who launched the weapons. But there might also be separate impacts, depending on who the combatants think fired the shots. So, it may be worth scurrying down the rabbit holes of straight or madcap logic to examine the possibilities.