feat(dist): bake the real Hudson app icon into the .app bundle

Package the deep-green Hudson mark (exported from the Pencil design) as a
full .icns (16→1024, @1x/@2x) and set CFBundleIconFile, so the installed
app shows the real logo in Dock/Finder/Launchpad instead of the generic
executable placeholder. The 1024 master is committed; package-app.sh builds
the iconset + .icns reproducibly at package time.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: mannasdev