Initial feature for drag / drop calendar events.

Wino.Mail.WinUI/Views/Calendar/CalendarPage.xaml

@@ -41,8 +41,10 @@
                 x:Name="CalendarSurface"
                 CalendarItems="{x:Bind ViewModel.CalendarItems, Mode=OneWay}"
                 CalendarSettings="{x:Bind ViewModel.CurrentSettings, Mode=OneWay}"
+                CalendarItemDropped="CalendarSurfaceCalendarItemDropped"
                 DefaultHourBackground="{ThemeResource CalendarDefaultHourBackgroundBrush}"
                 EmptySlotTapped="CalendarSurfaceEmptySlotTapped"
+                HoverSlotBackground="{ThemeResource CalendarHoverHourBackgroundBrush}"
                 IsEnabled="{x:Bind ViewModel.IsCalendarEnabled, Mode=OneWay}"
                 SelectedDateTime="{x:Bind ViewModel.SelectedQuickEventDate, Mode=OneWay}"
                 SelectedSlotBackground="{ThemeResource CalendarSelectedHourBackgroundBrush}"

Wino.Mail.WinUI/Views/Calendar/CalendarPage.xaml.cs

@@ -173,6 +173,9 @@ public sealed partial class CalendarPage : CalendarPageAbstract, ITitleBarSearch
         _suppressSelectionResetOnPopupClose = false;
     }
 
+    private async void CalendarSurfaceCalendarItemDropped(object sender, CalendarItemDroppedEventArgs e)
+        => await ViewModel.MoveCalendarItemAsync(e.CalendarItemViewModel, e.TargetStart);
+
     private void QuickEventAccountSelectorSelectionChanged(object sender, SelectionChangedEventArgs e)
         => QuickEventAccountSelectorFlyout.Hide();