imp: Bring back categories to library screen

Sorry guys for constant shifting.

lib/screens/florid_app.dart

@@ -1,6 +1,5 @@
 import 'package:florid/l10n/app_localizations.dart';
 import 'package:florid/models/fdroid_app.dart';
-import 'package:florid/screens/home/categories_screen.dart';
 import 'package:florid/screens/home/library_screen.dart';
 import 'package:florid/screens/settings/settings_screen.dart';
 import 'package:florid/screens/settings/user_screen.dart';
@@ -36,7 +35,7 @@ class _FloridAppState extends State<FloridApp> {
 
   late final List<Widget> _screens = [
     const LibraryScreen(),
-    CategoriesScreen(),
+    // CategoriesScreen(),
     SearchScreen(),
     UpdatesScreen(),
     UserScreen(),
@@ -497,11 +496,11 @@ class _FloridAppState extends State<FloridApp> {
                     selectedIcon: Icon(SolarIconsBold.home2),
                     label: localizations.home,
                   ),
-                  NavigationDestination(
-                    icon: Icon(SolarIconsOutline.widget_5),
-                    selectedIcon: const Icon(SolarIconsBold.widget_5),
-                    label: localizations.categories,
-                  ),
+                  // NavigationDestination(
+                  //   icon: Icon(SolarIconsOutline.widget_5),
+                  //   selectedIcon: const Icon(SolarIconsBold.widget_5),
+                  //   label: localizations.categories,
+                  // ),
                   NavigationDestination(
                     icon: Icon(SolarIconsOutline.roundedMagnifier),
                     selectedIcon: Icon(SolarIconsBold.roundedMagnifier),

lib/screens/home/categories_screen.dart

@@ -211,10 +211,6 @@ class _CategoriesScreenState extends State<CategoriesScreen>
         onRefresh: _onRefresh,
         child: CustomScrollView(
           slivers: [
-            SliverAppBar(
-              floating: true,
-              title: Text(AppLocalizations.of(context)!.categories),
-            ),
             SliverPadding(
               padding: const EdgeInsets.only(bottom: 16),
               sliver: SliverList(

lib/screens/home/library_screen.dart

@@ -33,7 +33,7 @@ class _LibraryScreenState extends State<LibraryScreen>
   @override
   void initState() {
     super.initState();
-    _tabController = TabController(length: 2, vsync: this);
+    _tabController = TabController(length: 3, vsync: this);
     _titleSwitchTimer = Timer(const Duration(seconds: 3), () {
       if (!mounted) return;
       setState(() {
@@ -71,7 +71,7 @@ class _LibraryScreenState extends State<LibraryScreen>
         newIndex = oldIndex + 1;
       }
 
-      final newLength = shouldShowTopApps ? 3 : 2;
+      final newLength = shouldShowTopApps ? 4 : 3;
       final clampedIndex = newIndex.clamp(0, newLength - 1);
 
       _tabController.dispose();
@@ -96,6 +96,7 @@ class _LibraryScreenState extends State<LibraryScreen>
     final localizations = AppLocalizations.of(context)!;
     final tabs = <Widget>[
       const HomeScreen(),
+      const CategoriesScreen(),
       if (_showTopAppsTab)
         AppSectionViewer(
           showAppBar: false,
@@ -181,7 +182,12 @@ class _LibraryScreenState extends State<LibraryScreen>
                   : Theme.of(context).colorScheme.surface,
               snap: true,
               floating: true,
-              shape: LinearBorder(bottom: LinearBorderEdge(), side: BorderSide(color: Theme.of(context).colorScheme.surfaceContainerLow)),
+              shape: LinearBorder(
+                bottom: LinearBorderEdge(),
+                side: BorderSide(
+                  color: Theme.of(context).colorScheme.surfaceContainerLow,
+                ),
+              ),
               bottom: PreferredSize(
                 preferredSize: Size.fromHeight(
                   settingsProvider.themeStyle == ThemeStyle.florid ? 64 : 56,
@@ -204,6 +210,10 @@ class _LibraryScreenState extends State<LibraryScreen>
                         icon: SolarIconsOutline.home,
                         label: AppLocalizations.of(context)!.home,
                       ),
+                      FloridTabBarItem(
+                        icon: SolarIconsOutline.widget_5,
+                        label: AppLocalizations.of(context)!.categories,
+                      ),
                       if (_showTopAppsTab)
                         FloridTabBarItem(
                           icon: SolarIconsOutline.courseUp,