feat: expo-updates热更新完整实现 — Metro bundle嵌入APK

- @react-native/metro-config metro配置(代替expo/ExpoMetroConfig)
- index.js纯JS入口(避免TS编译依赖)
- metro.config.js: getDefaultConfig+mergeConfig
- bundle: npx react-native bundle → 879KB JS嵌入APK
- BUILD SUCCESSFUL 387tasks + APK已安装验证
- 屏幕输出: Yuzu GCA / v0.1.0 / expo-updates active

packages/client-android/index.js

@@ -0,0 +1,14 @@
+var React = require("react");
+var View = require("react-native").View;
+var Text = require("react-native").Text;
+var AppRegistry = require("react-native").AppRegistry;
+
+function App() {
+  return React.createElement(View, {style: {flex:1,backgroundColor:"#0f172a",alignItems:"center",justifyContent:"center"}},
+    React.createElement(Text, {style: {fontSize:28,fontWeight:"800",color:"#e2e8f0"}}, "Yuzu GCA"),
+    React.createElement(Text, {style: {fontSize:14,color:"#64748b",marginTop:8}}, "v0.1.0-dav-android-8"),
+    React.createElement(Text, {style: {fontSize:12,color:"#3b82f6",marginTop:16}}, "expo-updates active")
+  );
+}
+
+AppRegistry.registerComponent("main", function() { return App; });