Adds a 'memory' subcommand and matching web tab that show how much of each
ESP32-C3 RAM window the guest has written, plus raw region dumps via QMP
pmemsave.
Split the emulator script into an xteink package so the CLI and the new
web UI share one QEMU driver. The web UI uploads firmware and an SD image,
boots them, drives the buttons, and long-polls the panel frame generation
so the screen updates on each e-ink refresh.