feat: add more detailed history and group per day

lib/utils/history_grouping.dart

@@ -0,0 +1,48 @@
+import '../models/closed_tab_item.dart';
+
+class ClosedTabItemDayGroup {
+  final DateTime day;
+  final List<ClosedTabItem> items;
+
+  const ClosedTabItemDayGroup({required this.day, required this.items});
+
+  int get itemCount => items.fold(
+    0,
+    (total, item) => total + (item.isRemoved ? 0 : item.quantity),
+  );
+}
+
+List<ClosedTabItemDayGroup> groupClosedTabItemsByDay(
+  Iterable<ClosedTabItem> items, {
+  required DateTime fallbackDate,
+}) {
+  final groups = <DateTime, List<ClosedTabItem>>{};
+
+  for (final item in items) {
+    final localPurchasedAt = (item.purchasedAt ?? fallbackDate).toLocal();
+    final day = DateTime(
+      localPurchasedAt.year,
+      localPurchasedAt.month,
+      localPurchasedAt.day,
+    );
+    groups.putIfAbsent(day, () => []).add(item);
+  }
+
+  for (final group in groups.values) {
+    group.sort((a, b) {
+      final aTime = (a.purchasedAt ?? fallbackDate).toLocal();
+      final bTime = (b.purchasedAt ?? fallbackDate).toLocal();
+      final byTime = bTime.compareTo(aTime);
+      if (byTime != 0) return byTime;
+
+      return b.id.compareTo(a.id);
+    });
+  }
+
+  final sortedGroups = groups.entries.toList()
+    ..sort((a, b) => b.key.compareTo(a.key));
+
+  return sortedGroups
+      .map((entry) => ClosedTabItemDayGroup(day: entry.key, items: entry.value))
+      .toList();
+}