Add ExpansionTileWithArrow class

This is like an ExpansionTile but always displays the expanding arrow even when `trailing` is specified

mobile/lib/common/expansion_tile_with_arrow.dart

@@ -0,0 +1,63 @@
+import 'package:flutter/material.dart';
+
+class ExpansionTileWithArrow extends StatefulWidget {
+  const ExpansionTileWithArrow(
+      {super.key,
+      required this.leading,
+      required this.title,
+      required this.subtitle,
+      required this.trailing,
+      required this.children});
+
+  final Widget leading;
+  final Widget title;
+  final Widget subtitle;
+  final Widget trailing;
+  final List<Widget> children;
+
+  @override
+  State<ExpansionTileWithArrow> createState() => _ExpansionTileWithArrowState();
+}
+
+class _ExpansionTileWithArrowState extends State<ExpansionTileWithArrow> with SingleTickerProviderStateMixin {
+  static final Animatable<double> _iconCurve = Tween<double>(begin: 0.0, end: 0.5).chain(CurveTween(curve: Curves.easeIn));
+  late Animation<double> _iconTurns;
+  late AnimationController _animationController;
+
+  @override
+  void initState() {
+    _animationController = AnimationController(duration: const Duration(milliseconds: 200), vsync: this);
+    _iconTurns = _animationController.drive(_iconCurve);
+    super.initState();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return ExpansionTile(
+      leading: widget.leading,
+      title: widget.title,
+      subtitle: widget.subtitle,
+      trailing: FittedBox(
+        child: Row(
+          children: [
+            widget.trailing,
+            RotationTransition(
+              turns: _iconTurns,
+              child: const Icon(Icons.expand_more),
+            )
+          ],
+        ),
+      ),
+      onExpansionChanged: (bool expanded) {
+        setState(() {
+          if (expanded) {
+            _animationController.forward();
+          } else {
+            _animationController.reverse();
+          }
+        });
+      },
+      children: widget.children,
+    );
+  }
+}