feat: add equality operators, make history screen paginated, random performance updates

lib/views/product_form_view.dart

@@ -36,6 +36,7 @@ class _ProductFormViewState extends State<ProductFormView> {
 
   Product? _existingProduct;
   String? _imagePath;
+  bool _hasImage = false;
   bool _isLoading = true;
   bool _isSaving = false;
 
@@ -72,6 +73,7 @@ class _ProductFormViewState extends State<ProductFormView> {
     _stockController.text = product.stockQuantity.toString();
     _lowStockController.text = product.lowStockThreshold.toString();
     _imagePath = product.imagePath;
+    _hasImage = product.imagePath != null && product.imagePath!.isNotEmpty;
 
     setState(() => _isLoading = false);
   }
@@ -108,10 +110,11 @@ class _ProductFormViewState extends State<ProductFormView> {
 
   Future<void> _pickImage() async {
     final pickedFile = await _imagePicker.pickImage(
-      source: ImageSource.gallery,
-      imageQuality: 85,
-      maxWidth: 1000,
-    );
+    source: ImageSource.gallery,
+    imageQuality: 80,
+    maxWidth: 1000,
+    maxHeight: 1000,
+  );
 
     if (pickedFile == null) return;
 
@@ -121,6 +124,7 @@ class _ProductFormViewState extends State<ProductFormView> {
 
     setState(() {
       _imagePath = copiedImagePath;
+      _hasImage = true;
     });
   }
 
@@ -222,7 +226,6 @@ class _ProductFormViewState extends State<ProductFormView> {
   }
 
   Widget _buildImagePicker(BuildContext context) {
-    final hasImage = _imagePath != null && File(_imagePath!).existsSync();
 
     return InkWell(
       onTap: _pickImage,
@@ -234,11 +237,22 @@ class _ProductFormViewState extends State<ProductFormView> {
           border: Border.all(color: Theme.of(context).colorScheme.outline),
         ),
         clipBehavior: Clip.antiAlias,
-        child: hasImage
+        child: _hasImage
             ? Stack(
                 fit: StackFit.expand,
                 children: [
-                  Image.file(File(_imagePath!), fit: BoxFit.fitHeight),
+                  Image.file(
+                    File(_imagePath!),
+                    fit: BoxFit.fitHeight,
+                    cacheWidth: 1000,
+                    errorBuilder: (context, error, stackTrace) => Center(
+                      child: Icon(
+                        Icons.broken_image_outlined,
+                        size: 48,
+                        color: Theme.of(context).colorScheme.outline,
+                      ),
+                    ),
+                  ),
                   Positioned(
                     right: 12,
                     bottom: 12,