refactor(notes): Improve code formatting and replace platform-specific refresh controls

lib/shared/widgets/loading_states.dart

@@ -433,23 +433,77 @@ class LoadingButton extends StatelessWidget {
   }
 }
 
-/// Refresh indicator with Conduit styling
+/// Refresh indicator with Conduit styling.
+///
+/// Uses platform-appropriate refresh controls:
+/// - iOS: Native Cupertino-style refresh control (when child is CustomScrollView)
+/// - Android/Other: Material RefreshIndicator
+///
+/// Set [edgeOffset] to position the indicator below an app bar or other
+/// overlay. For example, use `MediaQuery.of(context).padding.top + kToolbarHeight`
+/// to position below a transparent/floating app bar.
+///
+/// Note: On iOS with a CustomScrollView child, [edgeOffset] is ignored since
+/// CupertinoSliverRefreshControl naturally positions itself based on scroll
+/// content. The scroll view's existing padding should handle app bar clearance.
 class ConduitRefreshIndicator extends StatelessWidget {
   final Widget child;
   final Future<void> Function() onRefresh;
 
+  /// The distance from the top of the scroll view where the refresh indicator
+  /// will appear. Useful for positioning below a floating/transparent app bar.
+  ///
+  /// Note: This is only effective on Android/non-iOS platforms, or on iOS when
+  /// the child is not a CustomScrollView. For iOS with CustomScrollView, the
+  /// refresh control naturally positions based on scroll content.
+  final double edgeOffset;
+
   const ConduitRefreshIndicator({
     super.key,
     required this.child,
     required this.onRefresh,
+    this.edgeOffset = 0.0,
   });
 
   @override
   Widget build(BuildContext context) {
+    // On iOS, try to use CupertinoSliverRefreshControl for native feel
+    // when the child is directly a CustomScrollView
+    if (Platform.isIOS && child is CustomScrollView) {
+      final csv = child as CustomScrollView;
+      return CustomScrollView(
+        key: csv.key,
+        controller: csv.controller,
+        scrollDirection: csv.scrollDirection,
+        reverse: csv.reverse,
+        primary: csv.primary,
+        physics: csv.physics,
+        shrinkWrap: csv.shrinkWrap,
+        cacheExtent: csv.cacheExtent,
+        keyboardDismissBehavior: csv.keyboardDismissBehavior,
+        clipBehavior: csv.clipBehavior,
+        center: csv.center,
+        anchor: csv.anchor,
+        semanticChildCount: csv.semanticChildCount,
+        dragStartBehavior: csv.dragStartBehavior,
+        restorationId: csv.restorationId,
+        slivers: [
+          // CupertinoSliverRefreshControl naturally positions itself based on
+          // scroll content; the scroll view's existing padding handles app bar
+          // clearance, so no edgeOffset adjustment is needed here.
+          CupertinoSliverRefreshControl(onRefresh: onRefresh),
+          ...csv.slivers,
+        ],
+      );
+    }
+
+    // For Android, other platforms, or when child is not a CustomScrollView,
+    // use Material RefreshIndicator which works with any scrollable
     return RefreshIndicator(
       onRefresh: onRefresh,
       color: context.conduitTheme.buttonPrimary,
       backgroundColor: context.conduitTheme.surfaceBackground,
+      edgeOffset: edgeOffset,
       child: child,
     );
   }