Add About screen with 7-tap joelangel easter egg; fix deps

- About screen surfaces getAbout() content; tapping the title 7x reveals
  assets/joelangel.png (placeholder committed; replace with the real image)
- Correct UnifiedPush package to react-native-unifiedpush-connector (lazy-required)
- Fix expo-notifications NotificationBehavior (shouldShowAlert)
- Reachable via an ⓘ header button on the main tabs

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

app/src/navigation/RootNavigator.tsx

@@ -1,7 +1,10 @@
 import React from 'react';
-import { ActivityIndicator, View } from 'react-native';
-import { NavigationContainer } from '@react-navigation/native';
-import { createNativeStackNavigator } from '@react-navigation/native-stack';
+import { ActivityIndicator, Text, TouchableOpacity, View } from 'react-native';
+import { NavigationContainer, useNavigation } from '@react-navigation/native';
+import {
+  createNativeStackNavigator,
+  type NativeStackNavigationProp,
+} from '@react-navigation/native-stack';
 import { createBottomTabNavigator } from '@react-navigation/bottom-tabs';
 import { useAuth } from '@/auth/AuthContext';
 import { LoginScreen } from '@/screens/LoginScreen';
@@ -10,11 +13,13 @@ import { ScanScreen } from '@/screens/ScanScreen';
 import { FavoritesScreen } from '@/screens/FavoritesScreen';
 import { SessionsScreen } from '@/screens/SessionsScreen';
 import { MeterDetailScreen } from '@/screens/MeterDetailScreen';
+import { AboutScreen } from '@/screens/AboutScreen';
 import type { Zone } from 'parksmarter-client';
 
 export type RootStackParamList = {
   Tabs: undefined;
   MeterDetail: { zone: Zone };
+  About: undefined;
 };
 
 export type TabParamList = {
@@ -27,9 +32,20 @@ export type TabParamList = {
 const Stack = createNativeStackNavigator<RootStackParamList>();
 const Tab = createBottomTabNavigator<TabParamList>();
 
+function AboutButton() {
+  const navigation = useNavigation<NativeStackNavigationProp<RootStackParamList>>();
+  return (
+    <TouchableOpacity onPress={() => navigation.navigate('About')} style={{ paddingHorizontal: 12 }}>
+      <Text style={{ fontSize: 18 }}>ⓘ</Text>
+    </TouchableOpacity>
+  );
+}
+
 function Tabs() {
   return (
-    <Tab.Navigator screenOptions={{ headerShown: true }}>
+    <Tab.Navigator
+      screenOptions={{ headerShown: true, headerRight: () => <AboutButton /> }}
+    >
       <Tab.Screen name="Map" component={MapScreen} />
       <Tab.Screen name="Scan" component={ScanScreen} />
       <Tab.Screen name="Favorites" component={FavoritesScreen} />
@@ -59,6 +75,7 @@ export function RootNavigator() {
             component={MeterDetailScreen}
             options={{ title: 'Meter' }}
           />
+          <Stack.Screen name="About" component={AboutScreen} options={{ title: 'About' }} />
         </Stack.Navigator>
       ) : (
         <LoginScreen />