added support for simultan downloads in files and talk, support for background downloads, enhanced loading in files with retry

lib/main.dart

@@ -44,11 +44,13 @@ import 'storage/settings.dart';
 import 'theming/dark_app_theme.dart';
 import 'theming/light_app_theme.dart';
 import 'utils/app_paths.dart';
+import 'utils/downloads/download_manager.dart';
 import 'view/login/login.dart';
 import 'view/login/post_login_splash.dart';
 import 'widget/app_progress_indicator.dart';
 import 'widget/breaker/breaker.dart';
 import 'widget/debug/cache_view.dart';
+import 'widget/downloads/download_tray.dart';
 import 'widget_data/widget_sync.dart';
 
 Future<void> main() async {
@@ -98,6 +100,15 @@ Future<void> main() async {
   await PushRenderer.ensureChannels();
   FirebaseMessaging.onBackgroundMessage(pushOnBackgroundMessage);
 
+  // Wire up the native background downloader (progress notifications + tap
+  // handling) before the UI so a completion notification tapped during cold
+  // start is captured and opened once the downloads tray mounts.
+  unawaited(
+    DownloadManager.instance.initialize().onError(
+      (e, _) => log('DownloadManager init failed: $e'),
+    ),
+  );
+
   // Wire up the home-screen widget bridge before runApp so any widget render
   // triggered during startup hits initialised native storage.
   await WidgetSync.ensureInitialized();
@@ -285,8 +296,14 @@ class _MainState extends State<Main> {
           checkerboardRasterCacheImages:
               devToolsSettings.checkerboardRasterCacheImages,
           debugShowCheckedModeBanner: false,
+          navigatorKey: AppRoutes.rootNavigatorKey,
           // Used by ChatView.didPopNext to reclaim the global ChatBloc.
-          navigatorObservers: [AppRoutes.chatRouteObserver],
+          // DownloadRouteObserver tracks full-page navigations so the downloads
+          // chip only surfaces once the user leaves the screen they started on.
+          navigatorObservers: [
+            AppRoutes.chatRouteObserver,
+            DownloadRouteObserver(),
+          ],
           localizationsDelegates: const [
             ...GlobalMaterialLocalizations.delegates,
             GlobalWidgetsLocalizations.delegate,
@@ -304,7 +321,10 @@ class _MainState extends State<Main> {
           // black flash.
           builder: (context, child) => ColoredBox(
             color: LightAppTheme.marianumRed,
-            child: child ?? const SizedBox.shrink(),
+            // Downloads tray mounted ABOVE the navigator so its chip floats over
+            // every route (folder views, chat, viewer are full-page pushes that
+            // would otherwise cover it).
+            child: DownloadTrayHost(child: child ?? const SizedBox.shrink()),
           ),
           home: LoaderOverlay(
             child: Breaker(