Add mobile services, web proxy, and Gemma4 agent loop

- Mobile: add push notification and calendar sync services with full test suite (calendar, eventStore, notifications,
  screens)
- Mobile: add EAS build config and Jest setup
- Web: add API proxy, update useDestinationStation/useJourneys hooks, add middleware tests
- Web: update next.config and rebuild
- Agent: add Gemma4-based agent loop (agent_base, ttl_agent, ts_agent)
- Docs: add privacy policy, post-MVP plan, and aider rules

apps/mobile/App.tsx

@@ -1,5 +1,23 @@
+import { useEffect } from 'react';
+import * as Notifications from 'expo-notifications';
 import AppNavigator from './src/navigation/AppNavigator';
 
 export default function App() {
+  useEffect(() => {
+    // Request notification permissions on app start
+    Notifications.requestPermissionsAsync();
+
+    // Set up notification handler
+    Notifications.setNotificationHandler({
+      handleNotification: async () => ({
+        shouldShowAlert: true,
+        shouldPlaySound: true,
+        shouldSetBadge: false,
+        shouldShowBanner: true,
+        shouldShowList: true,
+      }),
+    });
+  }, []);
+
   return <AppNavigator />;
 }