feat: Add toast notifications and haptic feedback support

- Implemented ToastProvider for global toast notifications with different types (success, error, warning, info).
- Added haptic feedback utilities for various interaction types (light, medium, heavy, success, warning, error).
- Enhanced App.js to include ToastProvider for global access to toast notifications.
- Created EnhancedTextInput component with haptic feedback on focus and secure entry toggle.
- Developed GroupCard, ExpenseCard, MemberCard, and SummaryCard components with haptic feedback on interactions.
- Introduced skeleton loading components for GroupCard, ExpenseItem, and MemberItem.
- Added empty state components for groups, expenses, and friends with action prompts.
- Created themed icon buttons and action buttons with consistent styling.
- Implemented currency input with automatic formatting and search input with clear button functionality.

Author: Devasy

frontend/App.js

@@ -2,12 +2,15 @@ import { PaperProvider } from 'react-native-paper';
 import { AuthProvider } from './context/AuthContext';
 import AppNavigator from './navigation/AppNavigator';
 import { paperTheme } from './utils/theme';
+import { ToastProvider } from './utils/toast';
 
 export default function App() {
   return (
     <AuthProvider>
       <PaperProvider theme={paperTheme}>
-        <AppNavigator />
+        <ToastProvider>
+          <AppNavigator />
+        </ToastProvider>
       </PaperProvider>
     </AuthProvider>
   );

frontend/package-lock.json

@@ -16,6 +16,7 @@
     "@react-navigation/native-stack": "^7.3.23",
     "axios": "^1.11.0",
     "expo": "~53.0.20",
+    "expo-haptics": "^14.1.4",
     "expo-image-picker": "~16.0.2",
     "expo-linear-gradient": "^14.1.5",
     "expo-status-bar": "~2.2.3",