[Feature] Add PSU Control to Obico Web Client

[tardis89]

Is your feature request related to a problem? Please describe.
Currently, my OctoPrint installation has the PSU Control installed for my printer. This allows me to control a relay for controlling the power directly to my printer. As a result, when OctoPrint finishes a print, it then turns off the power to the printer. The serial connection can still work over USB, but all printer controls are disabled due to there being no power. Once the PSU Control is plugged in and configured, the relay will automatically turn on when a print is started, or can be turned ON/OFF manually with a button at the top fo the webpage. Since Obico does not have a button to turn this relay on/off, I am unable to access the printer remotely unless it has been manually started locally first through OctoPrint.

Describe the solution you'd like
It would be nice if Obico could connect to this and have a button within the web UI for turning the configured relay ON/OFF. The PSU control currently is only available through OctoPrint.

Describe alternatives you've considered
The only alternative I can think of is a hack of adding an ON/OFF button to another external means (HomeKit, HomeAssistant, etc.) but this would require going to another location in order for Obico to properly connect. Ideally, it can all be done within Obico itself.

The settings configuration page for the PSU Control plugin is below. The On/Off custom GCODE commands can be configured below.