feat: initialize Convert UI - browser-based file conversion app

- Add Next.js 16 with Turbopack and React 19
- Add Tailwind CSS 4 with OKLCH color system
- Implement FFmpeg.wasm for video/audio conversion
- Implement ImageMagick WASM for image conversion
- Add file upload with drag-and-drop
- Add format selector with fuzzy search
- Add conversion preview and download
- Add conversion history with localStorage
- Add dark/light theme support
- Support 22+ file formats across video, audio, and images

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

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

next.config.ts

@@ -0,0 +1,28 @@
+import type { NextConfig } from 'next';
+
+const nextConfig: NextConfig = {
+  output: 'export',
+  reactStrictMode: true,
+  // Turbopack configuration (Next.js 16+)
+  turbopack: {},
+  // Webpack fallback for older Next.js versions
+  webpack: (config) => {
+    // Required for FFmpeg.wasm and other WASM modules
+    config.resolve.fallback = {
+      ...config.resolve.fallback,
+      fs: false,
+      path: false,
+      crypto: false,
+    };
+
+    // Enable WASM
+    config.experiments = {
+      ...config.experiments,
+      asyncWebAssembly: true,
+    };
+
+    return config;
+  },
+};
+
+export default nextConfig;