0.9.0 - pressing the power button from a browser
The device can press the target's power and reset buttons now, and read its power LED back. No custom hardware: a two-channel PC817 optocoupler module does it, and the two machines stay electrically apart.
The console gets a Power panel with three actions: a click of the power button, a five second hold for a hard off, and a reset. It asks before the destructive ones.
The wiring is all settings, not a build: which GPIO pins you used, how long the pulse should be, which way round the module triggers. The same firmware runs on a board with nothing wired to it and says the feature is unavailable. If you guess the polarity wrong, that is a checkbox, not a reflash.
The wiring guide is in docs/wiring.md.