feat: Transform to Tauri desktop app

- Initialize Tauri v2 project with Rust backend
- Restructure project: move source files to src/ directory
- Add Tauri configuration for Windows, macOS, and Linux builds
- Update Vite config for Tauri development workflow
- Add file system and dialog permissions for native features
- Update package.json with desktop build scripts
- Update tsconfig.json paths for new src structure
- Add Tauri and desktop badges to README
- Document desktop build process and architecture

src-tauri/build.rs

@@ -0,0 +1,3 @@
+fn main() {
+  tauri_build::build()
+}