🐛 Fix navigation state loss

lib/main.dart

@@ -1,6 +1,7 @@
 import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
 import 'package:solian/providers/auth.dart';
+import 'package:solian/providers/navigation.dart';
 import 'package:solian/router.dart';
 import 'package:solian/utils/timeago.dart';
 import 'package:flutter_gen/gen_l10n/app_localizations.dart';
@@ -32,6 +33,7 @@ class SolianApp extends StatelessWidget {
             OverlayEntry(builder: (context) {
               return MultiProvider(
                 providers: [
+                  Provider(create: (_) => NavigationProvider()),
                   Provider(create: (_) => AuthProvider()),
                 ],
                 child: child,

lib/providers/navigation.dart

@@ -0,0 +1,3 @@
+class NavigationProvider {
+  int selectedIndex = 0;
+}

lib/widgets/navigation_drawer.dart

@@ -1,4 +1,6 @@
 import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
+import 'package:solian/providers/navigation.dart';
 import 'package:solian/router.dart';
 import 'package:flutter_gen/gen_l10n/app_localizations.dart';
 
@@ -14,9 +16,21 @@ class _SolianNavigationDrawerState extends State<SolianNavigationDrawer> {
 
   void _onSelect(String name, int idx) {
     setState(() => _selectedIndex = idx);
+    context.read<NavigationProvider>().selectedIndex = idx;
     router.goNamed(name);
   }
 
+  @override
+  void initState() {
+    Future.delayed(Duration.zero, () {
+      setState(() {
+        _selectedIndex = context.read<NavigationProvider>().selectedIndex;
+      });
+    });
+
+    super.initState();
+  }
+
   @override
   Widget build(BuildContext context) {
     final navigationItems = [