chore: make space nav bar narrower on mobile and ensure space nav bar matches user's theme

lib/pages/chat_list/navi_rail_item.dart

@@ -44,7 +44,11 @@ class NaviRailItem extends StatelessWidget {
                 bottom: 8,
                 left: 0,
                 child: AnimatedContainer(
-                  width: isSelected ? 8 : 0,
+                  width: isSelected
+                      ? FluffyThemes.isColumnMode(context)
+                          ? 8
+                          : 4
+                      : 0,
                   duration: FluffyThemes.animationDuration,
                   curve: FluffyThemes.animationCurve,
                   decoration: BoxDecoration(

lib/pages/settings/settings_view.dart

@@ -34,8 +34,7 @@ class SettingsView extends StatelessWidget {
         ?.tryGet<String>('account');
     return Row(
       children: [
-        if (FluffyThemes.isColumnMode(context) ||
-            AppConfig.displayNavigationRail) ...[
+        if (FluffyThemes.isColumnMode(context)) ...[
           SpacesNavigationRail(
             activeSpaceId: null,
             onGoToChats: () => context.go('/rooms'),