Ship logo (header + favicon) + bolder downline level labels

- Logo lockup (mint lightning/arrow icon + InstantAdPay wordmark) replaces the
  text wordmark in the back-office sidebar and public nav; icon added as the
  favicon on every page. Assets: /logo.png, /logo-icon.png.
- Downline level captions (LEVEL 1 / LEVEL 2 …) are now a bold mint pill instead
  of faint grey — far more readable.

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

public/shorts.html

@@ -4,7 +4,8 @@
 <meta charset="utf-8"><meta name="viewport" content="width=device-width,initial-scale=1">
 <title>Shorts | InstantAdPay</title>
 <link rel="stylesheet" href="https://fonts.googleapis.com/css2?family=Sora:wght@600;700;800&display=swap">
-<link rel="stylesheet" href="/assets/site.css?v=20260907v">
+<link rel="icon" type="image/png" href="/logo-icon.png">
+<link rel="stylesheet" href="/assets/site.css?v=20260908a">
 <style>
   html,body{height:100%;margin:0;overflow:hidden;background:#000}
   .sh{position:fixed;inset:0;display:flex;flex-direction:column;background:#000;color:var(--ink,#e8fff7)}