Initial commit: Next.js UWB positioning webapp

- Complete Next.js 14 app with TypeScript and Tailwind CSS
- ESP32 serial communication via API routes
- Real-time UWB positioning visualization
- Interactive 2D warehouse mapping with Canvas
- Device connection interface with auto-detection
- AT command parsing for UWBHelper library integration
- Clean project structure with comprehensive documentation

app/page.tsx

@@ -0,0 +1,22 @@
+import PositioningVisualizer from '@/components/PositioningVisualizer'
+
+export default function HomePage() {
+  return (
+    <main className="min-h-screen">
+      <header className="bg-white shadow-sm border-b">
+        <div className="max-w-6xl mx-auto px-6 py-6">
+          <h1 className="text-3xl font-bold text-gray-900">
+            UWB Indoor Positioning System
+          </h1>
+          <p className="text-gray-600 mt-2">
+            ESP32-S3 Warehouse Positioning & Visualization
+          </p>
+        </div>
+      </header>
+      
+      <div className="max-w-6xl mx-auto px-6 py-8">
+        <PositioningVisualizer />
+      </div>
+    </main>
+  )
+}