Align cyd_35r with CYD_PROJECT_GUIDE so ST7796 is not black-screened, LCD does not steal GT911 Wire, and firmware/docs match 22+21 wiring. Co-authored-by: Cursor <cursoragent@cursor.com>
PCF8574 backpack on SDA=GPIO22/SCL=GPIO27, demo/hello/clear/backlight UI, and flashable firmware/cyd package. Co-authored-by: Cursor <cursoragent@cursor.com>