png transparency support (#962)

* add png transparency support

text detection/ocr/inpaint transparency fixes 0.1

method 2 transparency fix

shapes + text block inpaint transparency fix

full page inpainting transparency fix

* fix and cleanup code generated by claude

---------

Co-authored-by: no <yeah@gmail.com>
Co-authored-by: dmMaze <beneathlimbo@gmail.com>