Add jpegdec and pngdec support to firmware

At the moment, the `gallery` app uses PNG loading and image blitting to display images.  While performant, for the Gallery application having access to [jpegdec](https://github.com/pimoroni/pimoroni-pico/tree/main/libraries/jpegdec) and [pngdec](https://github.com/pimoroni/pimoroni-pico/tree/main/libraries/pngdec) would make it much more user friendly to load images onto the badge.