Add Electron main process with token management and navigation setup

- Implement main and login windows for Electron.
- Integrate `electron-store` for secure token storage and management.
- Setup IPC handlers for authentication.
- Update dependencies to support Electron, including `vite`, `react-router-dom`, and plugins.

postcss.config.cjs

@@ -0,0 +1,5 @@
+module.exports = {
+  plugins: {
+    '@tailwindcss/postcss': {},
+  },
+}