* feat: redraw the app icon on a white tile with shorter bottom boxes
Same org chart shape as before, redrawn as a vector so edges are sharp.
The white tile keeps the icon visible on dark docks, taskbars and tabs,
so dark mode now uses the same image and favicon-white.svg is removed.
The desktop icon is now 1024x1024.
* chore: add SVG sources for the app icon and favicons
resources/icon.svg renders resources/icon.png; resources/favicon.svg renders
the favicon .ico and .png files.
* fix: add a title to the icon SVG sources for the Biome a11y check
