- public/icon.png and src/assets/logo.png were grayscale (mode L): a flat
white field, no alpha, which rendered as a white box/halo on every
non-white surface (window/taskbar icon, sidebar, launchers)
- regenerate both as RGBA: alpha is the ink coverage, RGB forced to 0 so
no white matte can leak through semi-transparent edge pixels
- styles.css: drop the white tile background/border-radius and cover-fit
from .sidebar-logo; the artwork now composites directly (contain-fit)
- originals preserved under deferred/original-icons/
