SLATE: a key-value engine for raw NOR flash that proves what happens when the power cuts mid-write

I've spent the last while building SLATE, a no_std, no-alloc key-value engine for the setting most storage engines quietly assume away: bare NOR flash, no filesystem underneath, no battery-backed cache, well under 100 KiB of RAM, and a supply rail that can die in the middle of a page program. Think ESP32-class microcontrollers up through small Linux boards. I wanted to share it here because the embedded category is exactly the crowd that runs into this problem, and I'd like feedback from people ...