feat: add basic screens for feed, invitations and profile

lib/screens/home_screen.dart

@@ -0,0 +1,51 @@
+import 'package:flutter/material.dart';
+import 'pages/feed_page.dart';
+import 'pages/invitations_page.dart';
+import 'pages/profile_page.dart';
+
+class HomeScreen extends StatefulWidget {
+  @override
+  _HomeScreenState createState() => _HomeScreenState();
+}
+
+class _HomeScreenState extends State<HomeScreen> {
+  int _currentIndex = 0;
+  
+  final List<Widget> _pages = [
+    FeedPage(),
+    InvitationsPage(),
+    ProfilePage(),
+  ];
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      body: _pages[_currentIndex],
+      bottomNavigationBar: BottomNavigationBar(
+        currentIndex: _currentIndex,
+        onTap: (index) {
+          setState(() {
+            _currentIndex = index;
+          });
+        },
+        type: BottomNavigationBarType.fixed,
+        selectedItemColor: Color(0xFF6A4C93),
+        unselectedItemColor: Colors.grey,
+        items: [
+          BottomNavigationBarItem(
+            icon: Icon(Icons.home),
+            label: 'Feed',
+          ),
+          BottomNavigationBarItem(
+            icon: Icon(Icons.mail),
+            label: 'Invitations',
+          ),
+          BottomNavigationBarItem(
+            icon: Icon(Icons.person),
+            label: 'Profile',
+          ),
+        ],
+      ),
+    );
+  }
+}

lib/screens/pages/feed_page.dart

@@ -0,0 +1,23 @@
+import 'package:flutter/material.dart';
+
+class FeedPage extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        title: Text('Feed'),
+        backgroundColor: Color(0xFF6A4C93),
+        foregroundColor: Colors.white,
+      ),
+      body: Center(
+        child: Text(
+          'This is the Feed Page',
+          style: TextStyle(
+            fontSize: 24,
+            fontWeight: FontWeight.w500,
+          ),
+        ),
+      ),
+    );
+  }
+}

lib/screens/pages/invitations_page.dart

@@ -0,0 +1,23 @@
+import 'package:flutter/material.dart';
+
+class InvitationsPage extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        title: Text('Invitations'),
+        backgroundColor: Color(0xFF6A4C93),
+        foregroundColor: Colors.white,
+      ),
+      body: Center(
+        child: Text(
+          'This is the Invitations Page',
+          style: TextStyle(
+            fontSize: 24,
+            fontWeight: FontWeight.w500,
+          ),
+        ),
+      ),
+    );
+  }
+}

lib/screens/pages/profile_page.dart

@@ -0,0 +1,23 @@
+import 'package:flutter/material.dart';
+
+class ProfilePage extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        title: Text('Profile'),
+        backgroundColor: Color(0xFF6A4C93),
+        foregroundColor: Colors.white,
+      ),
+      body: Center(
+        child: Text(
+          'This is the Profile Page',
+          style: TextStyle(
+            fontSize: 24,
+            fontWeight: FontWeight.w500,
+          ),
+        ),
+      ),
+    );
+  }
+}