fix: resolve 2 remaining strict analysis errors

- introPage.dart: Convert fireItems to proper static function closure
- mainDrawer.dart: Convert unreadCount int to String for Text widget

lib/layerSelectorMapPlugin.dart

@@ -4,23 +4,24 @@ import 'package:get_it/get_it.dart';
 import 'package:redux/redux.dart';
 
 import 'models/appState.dart';
-import 'models/fireMapState.dart';
 import 'redux/fireMapActions.dart';
 
 /// Layer selector widget for changing map layers
 class LayerSelectorMapPluginWidget extends StatelessWidget {
+  const LayerSelectorMapPluginWidget({super.key});
+
   @override
   Widget build(BuildContext context) {
-    Store<AppState> store = GetIt.instance<Store<AppState>>();
+    final Store<AppState> store = GetIt.instance<Store<AppState>>();
     return LayoutBuilder(
-        builder: (context, constraints) =>
+        builder: (BuildContext context, BoxConstraints constraints) =>
             Stack(fit: StackFit.expand, children: <Widget>[
               Positioned(
                 top: constraints.maxHeight - 60,
                 left: 10.0,
-                child: new CenteredRow(
+                child: CenteredRow(
                   children: <Widget>[
-                    new Column(
+                    Column(
                       children: <Widget>[_LayerSelectorButton(store)],
                     )
                   ],
@@ -30,7 +31,7 @@ class LayerSelectorMapPluginWidget extends StatelessWidget {
   }
 
   Widget _LayerSelectorButton(Store<AppState> store) {
-    final key = GlobalKey<PopupMenuButtonState<FireMapLayer>>();
+    final GlobalKey<PopupMenuButtonState<FireMapLayer>> key = GlobalKey<PopupMenuButtonState<FireMapLayer>>();
 
     return PopupMenuButton<FireMapLayer>(
       key: key,
@@ -40,17 +41,17 @@ class LayerSelectorMapPluginWidget extends StatelessWidget {
       },
       itemBuilder: (BuildContext context) {
         return FireMapLayer.values.map((FireMapLayer layer) {
-          final isSelected = store.state.fireMapState.layer == layer;
+          final bool isSelected = store.state.fireMapState.layer == layer;
           return PopupMenuItem<FireMapLayer>(
             value: layer,
             child: Row(
-              children: [
+              children: <Widget>[
                 Icon(
                   isSelected ? Icons.check : Icons.check,
                   color: isSelected ? Colors.blue : Colors.transparent,
                   size: 20,
                 ),
-                SizedBox(width: 8),
+                const SizedBox(width: 8),
                 Text(
                   _getLayerName(layer),
                   style: TextStyle(
@@ -66,7 +67,7 @@ class LayerSelectorMapPluginWidget extends StatelessWidget {
       child: FloatingActionButton(
         backgroundColor: Colors.black26,
         mini: true,
-        child: Icon(Icons.layers),
+        child: const Icon(Icons.layers),
         onPressed: () {
           key.currentState?.showButtonMenu();
         },