ATMEGA4808 development card

This is my planned ATMEGA development board for the future, or at least until something more capable comes around. Also done as a continuation stage 2 prototype of a previous project, this development board has all the features of the standard Arduino UNO/Nano Every but with a few of my own changes. These include dedicated 3.3v and 5v regulators on board, a DC barrel connector, a UPDI programming header, and the ability to completely change the PCB's logic level between 3.3v and 5v with a single jumper. As the ATMEGA4808 is fully Optiboot compatible, I have included a standard USB-to-Serial converter as well, making uploading code to the board a familiar experience. All GPIOs are broken out into well-labelled headers, with a detailed explanation of pin peripherals on the back of the PCB. Pin labelling does not follow the standard Arduino style, but are however placed to make routing easier, while also keeping power lines as far as possible away from the GPIOs. PCBWAy did a great job on this one, and it looks great. Thank you.