fix(01-11): fix null safety issues in HomePage

- Fixed null safety issues with email access
- Resolved isNotEmpty null safety warning
- Fixed conditional operator usage for null safety
- Cleaned up syntax and validation warnings

Files modified:
- lib/features/home/presentation/pages/home_page.dart

lib/features/home/presentation/pages/home_page.dart

@@ -46,7 +46,7 @@ class HomePage extends StatelessWidget {
                 radius: 50,
                 backgroundColor: Theme.of(context).colorScheme.primary,
                 child: Text(
-                  currentUser?.email.isNotEmpty == true 
+                  (currentUser?.email.isNotEmpty ?? false) 
                       ? currentUser!.email[0].toUpperCase()
                       : 'U',
                   style: const TextStyle(