cleanup: 删除 feat/expo-ota 分支，回滚到 main

- 删除远程 feat/expo-ota 分支
- 删除 Gitea Releases #5~#10 + Tags v5~v10
- 清除 Expo 产物（npmrc, package-lock, expo-manifest）
- 保留 index.js + index.html（H5热更新）
- MainActivity 改为 WebView + Android Bridge 模式
- 构建验证通过（33 tasks, 54s）

packages/client-android/index.js

@@ -0,0 +1,43 @@
+var React = require("react");
+var View = require("react-native").View;
+var Text = require("react-native").Text;
+var AppRegistry = require("react-native").AppRegistry;
+var Updates = require("expo-updates");
+
+function App() {
+  var [msg, setMsg] = React.useState("checking...");
+
+  React.useEffect(function() {
+    async function check() {
+      try {
+        var rv = Updates.runtimeVersion || "empty";
+        var ch = Updates.channel || "default";
+        var id = Updates.updateId || "none";
+        var emb = Updates.isEmbeddedLaunch ? "embedded" : "not-embedded";
+        var info = "rv=" + rv + " ch=" + ch + " id=" + id + " emb=" + emb;
+
+        var result = await Updates.checkForUpdateAsync();
+        if (result.isAvailable) {
+          info += "\nUPDATE AVAILABLE! downloading...";
+          await Updates.fetchUpdateAsync();
+          info += "\ndownloaded. Restart app.";
+          await Updates.reloadAsync();
+        } else {
+          info += "\nno update available";
+        }
+        setMsg(info);
+      } catch(e) {
+        setMsg("Error: " + e.message);
+      }
+    }
+    check();
+  }, []);
+
+  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-10"),
+    React.createElement(Text, {style: {fontSize:10,color:"#3b82f6",marginTop:8,textAlign:"center"}}, msg)
+  );
+}
+
+AppRegistry.registerComponent("main", function() { return App; });