chore: vendor client into main repo

client/app/index.tsx

@@ -0,0 +1,35 @@
+import { useEffect } from 'react';
+import { ActivityIndicator, StyleSheet, View } from 'react-native';
+import { useRouter } from 'expo-router';
+
+import { getOnboardingCompleted } from '@/src/storage/appStorage';
+
+/**
+ * 启动分发：根据 onboarding 状态跳转
+ */
+export default function Index() {
+  const router = useRouter();
+
+  useEffect(() => {
+    let cancelled = false;
+    (async () => {
+      const completed = await getOnboardingCompleted();
+      if (cancelled) return;
+      router.replace(completed ? '/(app)/home' : '/(onboarding)/onboarding');
+    })();
+    return () => {
+      cancelled = true;
+    };
+  }, [router]);
+
+  return (
+    <View style={styles.container}>
+      <ActivityIndicator />
+    </View>
+  );
+}
+
+const styles = StyleSheet.create({
+  container: { flex: 1, alignItems: 'center', justifyContent: 'center' },
+});
+