docs: add animated hero gif to README

[livlign]

Summary

Adds a 1200×675 animated hero GIF to the top of the README so visitors immediately see what viberank does — a multi-tool AI-coding usage leaderboard with stat cards, top rankings, and a "you" row climbing the board.

• Placed at public/hero.gif (1.3 MB, 18s loop, ~30fps) — matches the repo's static-asset convention
• Embedded after the tagline, before the existing badges
• Rebased onto current main (v2) — the hero now reads as multi-tool: subtitle is "ai coding leaderboard" and the rotating copy spans Claude Code, Codex, Gemini → one leaderboard rather than Claude Code alone
• Palette mirrors the app's dark + warm-orange theme
• All numbers are illustrative — no live stats baked in, so the image won't drift as the real leaderboard moves
• Alt text describes the content for screen-reader users

Test plan

• GIF renders cleanly in GitHub README preview
• File size under 10 MB (1.3 MB)
• Loop seam is clean
• Rebased on current main — no conflicts
• Asset at public/hero.gif
• Existing README content unchanged below the new line

---

Made with repo-visuals — a Claude Code skill for generating bespoke hero GIFs for GitHub repos.

[vercel]

@livlign is attempting to deploy a commit to the sculpt Team on Vercel.

A member of the Team first needs to authorize it.

[nikshepsvn]

Thanks — the hero GIF is a nice touch! Two small things before merge:

1. Could you rebase on current main? This branched off an older README (pre-v2), so the context lines are stale.
2. Please point the asset at public/hero.gif to match the repo's static-asset convention (there's no assets/ dir today).

Once rebased I'll merge. 🙏

[livlign]

Thanks! Both addressed:

1. Rebased onto current main — the stale pre-v2 context lines are gone; no conflicts now.
2. Asset moved to public/hero.gif to match the static-asset convention (no assets/ dir).

While rebasing I also refreshed the hero for v2 multi-tool: the subtitle now reads "ai coding leaderboard" and the rotating headline spans Claude Code, Codex, Gemini → one leaderboard instead of Claude Code alone, so it matches the new README. Ready for another look. 🙏