Modernize collaborative pixel art platform to production-ready architecture

Major refactor from simple HTML/JS app to modern full-stack TypeScript application:

## Architecture Changes
- Migrated to monorepo structure with workspaces (backend, frontend, shared)
- Backend: Node.js + Express + TypeScript + Socket.IO
- Frontend: Next.js 15.5 + React 19 + TypeScript + Tailwind CSS
- Shared: Common types and utilities across packages

## Key Features Implemented
- Real-time WebSocket collaboration via Socket.IO
- Virtual canvas with chunked loading for performance
- Modern UI with dark mode and responsive design
- Mock database system for easy development (Redis/PostgreSQL compatible)
- Comprehensive error handling and rate limiting
- User presence and cursor tracking
- Infinite canvas support with zoom/pan controls

## Performance Optimizations
- Canvas virtualization - only renders visible viewport
- Chunked pixel data loading (64x64 pixel chunks)
- Optimized WebSocket protocol
- Memory-efficient state management with Zustand

## Development Experience
- Full TypeScript support across all packages
- Hot reload for both frontend and backend
- Docker support for production deployment
- Comprehensive linting and formatting
- Automated development server startup

## Fixed Issues
- Corrected start script paths
- Updated environment configuration
- Fixed ESLint configuration issues
- Ensured all dependencies are properly installed
- Verified build process works correctly

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

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

frontend/src/components/ui/StatsOverlay.tsx

@@ -0,0 +1,69 @@
+'use client';
+
+import { motion } from 'framer-motion';
+
+interface StatsOverlayProps {
+  onlineUsers: number;
+  totalPixels: number;
+  zoom: number;
+}
+
+export function StatsOverlay({ onlineUsers, totalPixels, zoom }: StatsOverlayProps) {
+  return (
+    <motion.div
+      className="fixed top-4 left-4 sm:top-6 sm:left-6 z-50"
+      initial={{ opacity: 0, x: -30 }}
+      animate={{ opacity: 1, x: 0 }}
+      transition={{ 
+        type: "spring", 
+        stiffness: 400, 
+        damping: 25
+      }}
+    >
+      <motion.div 
+        className="bg-white/5 backdrop-blur-2xl rounded-xl sm:rounded-2xl p-3 sm:p-4 border border-white/20 shadow-lg ring-1 ring-white/10"
+        whileHover={{ 
+          scale: 1.05,
+          boxShadow: "0 10px 25px rgba(0,0,0,0.3)"
+        }}
+        transition={{ type: "spring", stiffness: 400, damping: 25 }}
+      >
+        <div className="space-y-2 sm:space-y-3">
+          <motion.div 
+            className="flex items-center gap-2 sm:gap-3"
+            initial={{ opacity: 0 }}
+            animate={{ opacity: 1 }}
+            transition={{ delay: 0.1 }}
+          >
+            <motion.div 
+              className="w-2.5 h-2.5 sm:w-3 sm:h-3 bg-green-400 rounded-full"
+              animate={{ 
+                scale: [1, 1.3, 1]
+              }}
+              transition={{ 
+                duration: 2,
+                repeat: Infinity,
+                ease: "easeInOut"
+              }}
+            />
+            <span className="text-white font-medium text-xs sm:text-sm">
+              {onlineUsers} online
+            </span>
+          </motion.div>
+          
+          <motion.div 
+            className="flex items-center gap-2 sm:gap-3"
+            initial={{ opacity: 0 }}
+            animate={{ opacity: 1 }}
+            transition={{ delay: 0.2 }}
+          >
+            <div className="w-2.5 h-2.5 sm:w-3 sm:h-3 bg-blue-400 rounded-full" />
+            <span className="text-white font-medium text-xs sm:text-sm">
+              {totalPixels.toLocaleString()} pixels
+            </span>
+          </motion.div>
+        </div>
+      </motion.div>
+    </motion.div>
+  );
+}