desktop: add electron version (#15663)

packages/desktop-electron/README.md

@@ -0,0 +1,32 @@
+# OpenCode Desktop
+
+Native OpenCode desktop app, built with Tauri v2.
+
+## Development
+
+From the repo root:
+
+```bash
+bun install
+bun run --cwd packages/desktop tauri dev
+```
+
+This starts the Vite dev server on http://localhost:1420 and opens the native window.
+
+If you only want the web dev server (no native shell):
+
+```bash
+bun run --cwd packages/desktop dev
+```
+
+## Build
+
+To create a production `dist/` and build the native app bundle:
+
+```bash
+bun run --cwd packages/desktop tauri build
+```
+
+## Prerequisites
+
+Running the desktop app requires additional Tauri dependencies (Rust toolchain, platform-specific libraries). See the [Tauri prerequisites](https://v2.tauri.app/start/prerequisites/) for setup instructions.