Nafiz-365/cf-visualizer-project ? reverse-engineered prompt

Build me a full stack Codeforces visualizer web app that lets people search a Codeforces handle and see a clean dashboard with their rating history, contest activity, verdict breakdown, solved problem levels, and a heatmap of daily activity.

I also want an AI coach that can explain weak spots, summarize contests, and give advice based on a user’s submissions and tags. Add login and signup, save user data safely, and let people bookmark problems, leave short notes, and keep track of unsolved problems they want to come back to later.

It should also support comparing two or more handles side by side, a simple friends or leaderboard view, and a way to export a profile card image for sharing. Please make it responsive, support dark mode, and use mock or fallback data if the Codeforces API is slow or unavailable. Look up current docs online if you need to.