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/src/main.rs

@@ -0,0 +1,6 @@
+// Prevents additional console window on Windows in release, DO NOT REMOVE!!
+#![cfg_attr(not(debug_assertions), windows_subsystem = "windows")]
+
+fn main() {
+  app_lib::run();
+}