feat(accessibility): add reduceMotion scaling and minimize animations; apply RepaintBoundary to heavy widgets

lib/widgets/dialogs/delete_confirmation_dialog.dart

@@ -1,5 +1,6 @@
 import 'package:flutter/material.dart';
 import 'dart:ui';
+import '../../utils/reduce_motion.dart';
 import '../../theme/app_colors.dart';
 import '../common/buttons/primary_button.dart';
 import '../common/buttons/secondary_button.dart';
@@ -27,7 +28,10 @@ class DeleteConfirmationDialog extends StatelessWidget {
             ClipRRect(
               borderRadius: BorderRadius.circular(24),
               child: BackdropFilter(
-                filter: ImageFilter.blur(sigmaX: 10, sigmaY: 10),
+                filter: ImageFilter.blur(
+                  sigmaX: ReduceMotion.scale(context, normal: 10, reduced: 4),
+                  sigmaY: ReduceMotion.scale(context, normal: 10, reduced: 4),
+                ),
                 child: Container(
                   decoration: BoxDecoration(
                     color: AppColors.glassCard.withValues(alpha: 0.8),