Fix public file viewer compilation errors and add PDF styling

- Add missing imports for SfPdfViewer and Uint8List
- Fix _initializeVideoPlayer method declaration
- Correct SfTheme import to use syncfusion_flutter_core/theme.dart
- Restore PDF bytes loading via API for public shares
- Add SfTheme wrapper for PDF viewer styling

b0esche_cloud/lib/pages/public_file_viewer.dart

@@ -2,7 +2,9 @@ import 'package:flutter/material.dart';
 import 'package:go_router/go_router.dart';
 import 'package:web/web.dart' as web;
 import 'dart:ui_web' as ui_web;
-import 'package:syncfusion_flutter_theme/syncfusion_flutter_theme.dart';
+import 'package:syncfusion_flutter_core/theme.dart';
+import 'package:syncfusion_flutter_pdfviewer/pdfviewer.dart';
+import 'dart:typed_data';
 import 'package:video_player/video_player.dart';
 import 'package:flutter/foundation.dart' show kIsWeb;
 import '../theme/app_theme.dart';
@@ -88,6 +90,8 @@ class _PublicFileViewerState extends State<PublicFileViewer> {
       }
     }
   }
+
+  Future<void> _initializeVideoPlayer() async {
     if (!kIsWeb) {
       // For mobile, use VideoPlayerController
       final url = _fileData?['viewUrl'] ?? _fileData?['downloadUrl'];