feat: add toast notifications, random font, and font info display

Major UX enhancements for better user feedback and discovery:

**Toast Notification System**
- Beautiful toast notifications with 3 types (success/error/info)
- Auto-dismiss after 3 seconds
- Slide-in animation from right
- Color-coded by type (green/red/blue)
- Dark mode support
- Close button for manual dismiss
- ToastProvider context for global access
- Non-blocking UI overlay

**Random Font Discovery**
- Shuffle button in font selector
- One-click random font selection
- Toast notification shows selected font
- Perfect for discovering new fonts
- Located next to "Select Font" header

**Enhanced Font Preview**
- Font name badge display
- Character count statistics
- Line count statistics
- Better visual hierarchy
- Responsive stat display

**Improved Feedback**
- Toast on copy: "Copied to clipboard!"
- Toast on share: "Shareable URL copied!"
- Toast on random: "Random font: FontName"
- Error toasts for failed operations
- Removed temporary text replacement

**Smooth Animations**
- Slide-in animation for toasts
- Fade-in animation class
- Custom keyframe animations
- CSS utility classes
- Smooth transitions throughout

**Technical Improvements**
- useToast custom hook
- Context-based state management
- Auto-cleanup with setTimeout
- Unique toast IDs
- TypeScript types for toast system
- Proper event propagation

**Better UX**
- No more jarring text replacements
- Non-intrusive notifications
- Professional feedback system
- Discoverable random feature
- Informative preview stats

The app now feels polished and professional with proper user feedback!

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

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

app/globals.css

@@ -107,3 +107,24 @@
     @apply bg-muted-foreground/20 rounded-lg hover:bg-muted-foreground/30;
   }
 }
+
+@layer utilities {
+  .animate-in {
+    animation: fadeIn 0.2s ease-in;
+  }
+
+  .slide-in-from-right-full {
+    animation: slideInFromRight 0.3s ease-out;
+  }
+}
+
+@keyframes slideInFromRight {
+  from {
+    transform: translateX(100%);
+    opacity: 0;
+  }
+  to {
+    transform: translateX(0);
+    opacity: 1;
+  }
+}