perf: sag tik efekt suruklemesinde kitlenme fix — image provider memoize (her frame'de yeniden decode onlendi)

lib/widgets/image_canvas.dart

@@ -338,13 +338,23 @@ class _ImageCanvasState extends State<ImageCanvas> {
     return _cachedFilter!;
   }
 
+  FileImage? _cachedFileImage;
+  ImageProvider<Object>? _cachedProvider;
+  String? _cachedPath;
+  int? _cachedCacheWidth;
+
   Widget _buildImage() {
     final longest = _vpSize.longestSide;
     final cacheWidth = longest > 0 ? (longest * 2).round() : null;
-    final ImageProvider<Object> provider = cacheWidth != null
+    if (_cachedPath != widget.filePath || _cachedCacheWidth != cacheWidth) {
-        ? ResizeImage.resizeIfNeeded(
+      _cachedPath = widget.filePath;
-            cacheWidth, null, FileImage(File(widget.filePath)))
+      _cachedCacheWidth = cacheWidth;
-        : FileImage(File(widget.filePath));
+      _cachedFileImage = FileImage(File(widget.filePath));
+      _cachedProvider = cacheWidth != null
+          ? ResizeImage.resizeIfNeeded(cacheWidth, null, _cachedFileImage!)
+          : null;
+    }
+    final ImageProvider<Object> provider = _cachedProvider ?? _cachedFileImage!;
     return Image(
       key: _imageKey,
       image: provider,