Adds LICENSE-MIT, LICENSE-APACHE and docs/brand/LICENSE-brand.txt from the Crafting Apps
licensing standard. NOTICE follows the standard template (copyright, licence, brand carve-out)
and keeps the third-party list, now noting the Feather-derived Lucide icons (also MIT) and the
egui default fonts compiled into the app. ASSETS.md gives the docs/brand/ files their trademark
terms and marks the 21 Feather-derived Lucide icons. README uses the standard License and credits
section; AGENTS.md/CLAUDE.md point to the licence and brand files.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>