sheets view: add refresh button for annotations

lib/core/services/annotation_sync_service.dart

@@ -15,24 +15,26 @@ class AnnotationSyncService {
   AnnotationSyncService({
     required ApiClient apiClient,
     required StorageService storageService,
-  })  : _apiClient = apiClient,
-        _storageService = storageService;
+  }) : _apiClient = apiClient,
+       _storageService = storageService;
 
   /// Downloads annotations from server and merges with local storage.
   ///
   /// For each page, compares server's lastModified with local lastModified.
   /// If server is newer, overwrites local. Local annotations that are newer
   /// are preserved.
-  Future<void> syncFromServer(String sheetUuid) async {
+  Future<void> syncAnnotationsFromServer(String sheetUuid) async {
     try {
       _log.info('Syncing annotations from server for sheet $sheetUuid');
 
       // Fetch all annotations from server
       final serverAnnotations = await _apiClient.fetchAnnotations(sheetUuid);
 
+      _log.fine('Fetched annotations from server for sheet $sheetUuid');
+
       // Get all local annotations with metadata
-      final localAnnotations =
-          await _storageService.readAllAnnotationsWithMetadata(sheetUuid);
+      final localAnnotations = await _storageService
+          .readAllAnnotationsWithMetadata(sheetUuid);
 
       int updatedCount = 0;
 
@@ -118,7 +120,8 @@ class AnnotationSyncService {
       return false;
     } catch (e) {
       _log.warning(
-          'Unexpected error uploading annotation, queuing for later: $e');
+        'Unexpected error uploading annotation, queuing for later: $e',
+      );
       await _queueForLaterUpload(
         sheetUuid: sheetUuid,
         page: page,

lib/features/sheet_viewer/sheet_viewer_page.dart

@@ -40,6 +40,7 @@ class _SheetViewerPageState extends State<SheetViewerPage>
 
   PdfDocument? _document;
   late Future<bool> _documentLoaded;
+  late Future<void> _annotationsLoaded;
   int _currentPage = 1;
   int _totalPages = 1;
   bool _isPaintMode = false;
@@ -69,6 +70,15 @@ class _SheetViewerPageState extends State<SheetViewerPage>
       FullScreen.setFullScreen(widget.config.fullscreen);
     }
     _documentLoaded = _loadPdf();
+    _syncAnnotations();
+  }
+
+  void _syncAnnotations() {
+    setState(() {
+      _annotationsLoaded = _syncService.syncAnnotationsFromServer(
+        widget.sheet.uuid,
+      );
+    });
   }
 
   @override
@@ -97,20 +107,22 @@ class _SheetViewerPageState extends State<SheetViewerPage>
     } else {
       // Native: use file cache
       final file = await widget.apiClient.getPdfFileCached(widget.sheet.uuid);
+      _log.fine("Found file, opening...");
       _document = await PdfDocument.openFile(file.path);
       widget.sheet.availableOffline = true;
     }
 
+    _log.fine("Pdf loaded");
+
     setState(() {
       _totalPages = _document!.pages.length;
     });
 
-    // Sync annotations from server (downloads newer versions)
-    await _syncService.syncFromServer(widget.sheet.uuid);
-
     // Load annotations for current page(s)
     await _loadAnnotationsForCurrentPages();
 
+    _log.fine("Annotations loaded");
+
     return true;
   }
 
@@ -304,6 +316,26 @@ class _SheetViewerPageState extends State<SheetViewerPage>
               : 'Enter Fullscreen',
           onPressed: _toggleFullscreen,
         ),
+        FutureBuilder<void>(
+          future: _annotationsLoaded,
+          builder: (context, snapshot) {
+            if (snapshot.hasError) {
+              _log.warning('Error loading annotations', snapshot.error);
+              return IconButton(
+                onPressed: _syncAnnotations,
+                icon: Icon(Icons.error, color: Colors.red),
+              );
+            }
+            if (snapshot.connectionState == ConnectionState.done) {
+              _loadAnnotationsForCurrentPages();
+              return IconButton(
+                onPressed: _syncAnnotations,
+                icon: Icon(Icons.refresh),
+              );
+            }
+            return const CircularProgressIndicator();
+          },
+        ),
         IconButton(
           icon: Icon(_isPaintMode ? Icons.brush : Icons.brush_outlined),
           tooltip: _isPaintMode ? 'Exit Paint Mode' : 'Enter Paint Mode',