[#43] App: Use FileSystemWatcher to renew contexts on demand

Elwig/Windows/DeliveryAdminWindow.xaml.cs

@@ -795,9 +795,8 @@ namespace Elwig.Windows {
             StatusVarieties.ToolTip = StatusVarieties.Text;
         }
 
-        protected override async Task OnRenewContext() {
-            await base.OnRenewContext();
-            using var ctx = new AppDbContext();
+        protected override async Task OnRenewContext(AppDbContext ctx) {
+            await base.OnRenewContext(ctx);
 
             if (Member != null) {
                 if (await GetMemberAsync(Member.MgNr) is not Member m) {