coo-ona/cooViewer — reverse-engineered prompt

Build me a simple native Mac comic viewer that feels lightweight and polished.

I want to be able to open comic files and image archives like CBZ, CBR, ZIP, RAR, PDF, and normal image folders, then read page by page with smooth keyboard controls. Give it a main reader view, a thumbnail browser, fullscreen reading, zoom, fit to window, bookmarks, and a few basic preferences. It should remember the last page I was on, show the right file icons in Finder, and handle empty or broken images without crashing.

Please make it feel like a real macOS app, not a web wrapper. Use the existing artwork, icons, and localized text that are already in the project, and keep both English and Japanese support if possible. If there is an existing manual or behavior reference online, use that as the source of truth and fill in any missing details from there.