feat: add Figlet ASCII art generator as 7th tool

- Added Figlet tool with 373 fonts for ASCII art text generation
- Created new gradient-yellow-amber for terminal/retro aesthetic
- Updated Stats component from 6 to 7 tools
- Updated Footer badge to 7 tools and added Figlet link
- Added Figlet to README Available Tools section

Figlet Features:
- 373 curated fonts from xero/figlet-fonts collection
- Live preview and fuzzy search
- Multiple export formats (text, PNG, SVG, code snippets)
- Shareable URLs and keyboard shortcuts
- Perfect for ASCII banners, terminal art, and retro designs

Color: Yellow (#eab308) to Amber (#f59e0b) gradient
URL: https://figlet.kit.pivoine.art

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

components/Stats.tsx

@@ -4,7 +4,7 @@ import { motion } from 'framer-motion';
 
 const stats = [
   {
-    number: '6',
+    number: '7',
     label: 'Tools',
     icon: (
       <svg className="w-6 h-6" fill="none" stroke="currentColor" viewBox="0 0 24 24">