Add initial JSON data files and implement core page components for game functionality

app/components/MemberFooterNavbar.jsx

@@ -0,0 +1,49 @@
+import React from 'react';
+import { View, Pressable, Text, StyleSheet } from 'react-native';
+import { useNavigation } from '@react-navigation/native';
+
+const MemberFooterNavbar = ({ visible = false }) => {
+  const navigation = useNavigation();
+
+  if (!visible) {
+    return null;
+  }
+
+  return (
+    <View style={styles.container}>
+      <Pressable style={styles.button} onPress={() => navigation.navigate('game-lobby')}>
+        <Text style={styles.text}>Lobby</Text>
+      </Pressable>
+      <Pressable style={styles.button} onPress={() => navigation.navigate('team')}>
+        <Text style={styles.text}>Team</Text>
+      </Pressable>
+      <Pressable style={styles.button} onPress={() => navigation.navigate('map')}>
+        <Text style={styles.text}>Map</Text>
+      </Pressable>
+    </View>
+  );
+};
+
+const styles = StyleSheet.create({
+  container: {
+    flexDirection: 'row',
+    justifyContent: 'space-between',
+    borderTopWidth: 1,
+    borderColor: '#d4d4d8',
+    paddingHorizontal: 16,
+    paddingVertical: 10,
+    backgroundColor: '#ffffff',
+  },
+  button: {
+    flex: 1,
+    alignItems: 'center',
+  },
+  text: {
+    fontSize: 14,
+    fontWeight: '600',
+    color: '#111827',
+  },
+});
+
+export default MemberFooterNavbar;
+