feat: v5 — boxing poster fight cards, 12-char names, diverse mock bots

- Fight Card page: dramatic poster background with cross-hatch, spotlights,
  vignettes, corner brackets, scan lines; 3D VS orb with punch animation;
  selectable undercard with main event always pinned at top
- PosterSprite: high-quality 480px poster frame with 6-pass renderer
  (aura, glow, bevel, specular, particles); PixelGlove component
- 12-char bot name limit across all forms and server validation
- Mock bots: all 100 now have diverse archetypes (25 types), 25% human
  fighters; seedMockBots updates existing bots on restart
- Leaderboard: inline SpritePreview next to each bot name
- Nostr auth: persistent login, nsec copy button
- Wallet: NWC + Lightning Address, ranked fight flow
- Server: payments, ranked queue, customization endpoint

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/index.html

@@ -9,7 +9,7 @@
     <link rel="icon" href="/favicon.ico" sizes="32x32" />
     <link rel="icon" href="/icon.svg" type="image/svg+xml" />
     <link rel="apple-touch-icon" href="/apple-touch-icon.png" />
-    <meta name="apple-mobile-web-app-capable" content="yes" />
+    <meta name="mobile-web-app-capable" content="yes" />
     <meta name="apple-mobile-web-app-status-bar-style" content="black-translucent" />
     <meta name="apple-mobile-web-app-title" content="BOTFIGHTS" />
     <link rel="preconnect" href="https://fonts.googleapis.com" />