Our icon sources currently include two versions of the Blender logo, the official one and one that is modified to align better to our smallest pixel grid. But with our recent change to SVG icons, and alignment tweaks to the official version this can be used in all cases. This PR does so, removes BLENDER_LARGE, and also slightly tweaks FILE_BACKUP and FILE_BLEND to use the official form. Pull Request: https://projects.blender.org/blender/blender/pulls/124179