flipperdevices/flipperone-mcu-firmware ? reverse-engineered prompt

Build me the MCU firmware for Flipper One, the low power RP2350 side that handles the LCD, buttons, touchpad, LEDs, battery, and power control.

I want a project that can compile into a UF2 file and be flashed to an RP2350 board or the Flipper One device. Keep the default board target as f1, but make it easy to switch targets later. Please wire up the basic firmware structure so it can talk to the main Linux CPU over SPI, I2C, UART, and the needed GPIO signals, and make sure the build works cleanly from VSCode with the Pico tooling or with CMake from the command line.

If you need current setup details or SDK docs, look them up online and follow the latest recommended approach. I’d also like a simple, practical README for building and flashing it, since the current one looks incomplete.