brisma/gbsc-pro ? reverse-engineered prompt

Build me the firmware and support tools for a GBSC Pro video upscaler, so it can take retro console video and turn it into clean HDMI output with low latency. I want the main controller firmware to handle input switching, on screen menus, web based settings, saved profiles, scanlines, color and brightness controls, and communication with the secondary video controller.

Also build the secondary firmware for the video decoder and encoder, plus a simple desktop utility to inspect and tweak the video chip settings over serial, and a flashing tool that can update both firmwares from one place. Keep it practical and usable, with good defaults, clear menus, and persistent settings. If anything is unclear, use the README and look up current docs online if you need to.