feat: add initState logging to downloads screen

Added missing logging in DownloadsScreen.initState():
- 📥 Log initState() call
- 📥 Log postFrameCallback triggered
- 📥 Log before calling refreshDownloads()

This completes the logging chain to track full initialization flow.

lib/presentation/screens/downloads/downloads_screen.dart

@@ -16,7 +16,10 @@ class _DownloadsScreenState extends State<DownloadsScreen> {
   @override
   void initState() {
     super.initState();
+    print('📥 DownloadsScreen: initState() called');
     WidgetsBinding.instance.addPostFrameCallback((_) {
+      print('📥 DownloadsScreen: postFrameCallback triggered');
+      print('📥 DownloadsScreen: calling refreshDownloads()');
       context.read<DownloadsProvider>().refreshDownloads();
     });
   }