feat(gateway): integrate OpenClaw as git submodule

- Add OpenClaw as git submodule at ./openclaw/
- Update GatewayManager to start gateway from submodule path
- Support both production (dist) and development (pnpm dev) modes
- Add IPC handler for OpenClaw status check
- Update Setup wizard to check real OpenClaw submodule status
- Configure electron-builder to include submodule in packaged app
- Add npm scripts for submodule management:
  - postinstall: auto-init submodule
  - openclaw:init: initialize and install dependencies
  - openclaw:install: install dependencies only
  - openclaw:build: build OpenClaw
  - openclaw:update: update to latest version

package.json

@@ -38,7 +38,12 @@
     "publish:mac": "electron-builder --mac --publish always",
     "publish:win": "electron-builder --win --publish always",
     "publish:linux": "electron-builder --linux --publish always",
-    "release": "pnpm run build:vite && pnpm run publish"
+    "release": "pnpm run build:vite && pnpm run publish",
+    "postinstall": "git submodule update --init",
+    "openclaw:init": "git submodule update --init && cd openclaw && pnpm install",
+    "openclaw:install": "cd openclaw && pnpm install",
+    "openclaw:build": "cd openclaw && pnpm build",
+    "openclaw:update": "git submodule update --remote openclaw && cd openclaw && pnpm install"
   },
   "dependencies": {
     "electron-store": "^10.0.0",