feat: add Electron desktop application support

- Add electron/ directory with main process, preload script, and types
- Add system tray integration and window management
- Add IPC communication for app info, external links, server controls
- Add useElectron React hooks for Next.js integration
- Add build scripts for Windows, macOS, and Linux
- Add development scripts for running Electron with Next.js

Ref: #149

electron/README.md

@@ -0,0 +1,150 @@
+# OmniRoute Electron Desktop App
+
+This directory contains the Electron desktop application wrapper for OmniRoute.
+
+## Structure
+
+```
+electron/
+├── main.js          # Main process (window management, IPC)
+├── preload.js       # Preload script (secure bridge to renderer)
+├── package.json     # Electron-specific dependencies
+├── types.d.ts       # TypeScript definitions
+└── assets/          # Application icons and resources
+```
+
+## Development
+
+### Prerequisites
+
+1. Build the Next.js app first:
+```bash
+npm run build
+```
+
+2. Install Electron dependencies:
+```bash
+cd electron
+npm install
+```
+
+### Running in Development
+
+1. Start the Next.js development server:
+```bash
+npm run dev
+```
+
+2. In another terminal, start Electron:
+```bash
+cd electron
+npm run dev
+```
+
+### Running in Production Mode
+
+1. Build Next.js in standalone mode:
+```bash
+npm run build
+```
+
+2. Start Electron:
+```bash
+cd electron
+npm start
+```
+
+## Building
+
+### Build for Current Platform
+```bash
+cd electron
+npm run build
+```
+
+### Build for Specific Platforms
+
+```bash
+# Windows
+npm run build:win
+
+# macOS
+npm run build:mac
+
+# Linux
+npm run build:linux
+```
+
+## Output
+
+Built applications are placed in `dist-electron/`:
+- Windows: `.exe` installer (NSIS)
+- macOS: `.dmg` installer
+- Linux: `.AppImage`
+
+## Features
+
+- **System Tray Integration**: Minimize to tray, quick actions
+- **Native Notifications**: Desktop notifications
+- **Window Management**: Minimize, maximize, close
+- **Auto-start**: Option to launch on system startup
+- **Offline Support**: Local server bundled with the app
+
+## Configuration
+
+### Environment Variables
+
+The Electron app respects these environment variables:
+- `OMNIROUTE_PORT`: Server port (default: 20128)
+- `NODE_ENV`: Set to 'production' for production builds
+
+### Custom Icon
+
+Place your icons in `assets/`:
+- `icon.ico` - Windows icon (256x256)
+- `icon.icns` - macOS icon bundle
+- `icon.png` - Linux/general use (512x512)
+- `tray-icon.png` - System tray icon (16x16 or 32x32)
+
+## IPC Channels
+
+| Channel | Direction | Description |
+|---------|-----------|-------------|
+| `get-app-info` | Renderer → Main | Get app name, version, platform |
+| `open-external` | Renderer → Main | Open URL in default browser |
+| `get-data-dir` | Renderer → Main | Get data directory path |
+| `restart-server` | Renderer → Main | Restart the internal server |
+| `server-status` | Main → Renderer | Server status updates |
+| `port-changed` | Main → Renderer | Port change notifications |
+
+## Security
+
+- `contextIsolation: true` - Isolates renderer from Node.js
+- `nodeIntegration: false` - No direct Node.js access in renderer
+- Preload script validates IPC channels
+- No remote code execution
+
+## Troubleshooting
+
+### App Won't Start
+
+1. Check if port 20128 is available
+2. Check logs in the console
+3. Verify the build output exists
+
+### White Screen
+
+1. Verify Next.js build exists
+2. Check the server URL in main.js
+3. Check for console errors
+
+### Build Fails
+
+1. Ensure you have build tools installed:
+   - Windows: Visual Studio Build Tools
+   - macOS: Xcode Command Line Tools
+   - Linux: build-essential, libsecret-1-dev
+
+## License
+
+MIT