Enhance AuditView and NavMenu: restrict access for non-admin users in InitializeDataAsync and OnReadData methods, and refactor NavMenu structure for better readability

Co-authored-by: Copilot <copilot@github.com>

FoodsharingSiegen.Server/Pages/AuditView.razor.cs

@@ -1,5 +1,6 @@
 using Blazorise.DataGrid;
 using FoodsharingSiegen.Contracts.Entity;
+using FoodsharingSiegen.Contracts.Helper;
 using FoodsharingSiegen.Server.Data.Service;
 using Microsoft.AspNetCore.Components;
 
@@ -39,6 +40,7 @@ namespace FoodsharingSiegen.Server.Pages
         /// <inheritdoc />
         protected override Task InitializeDataAsync()
         {
+            if (!CurrentUser.IsAdmin()) NavigationManager.NavigateTo("/");
             return Task.CompletedTask;
         }
 
@@ -52,6 +54,8 @@ namespace FoodsharingSiegen.Server.Pages
         /// <param name="e">The params</param>
         private async Task OnReadData(DataGridReadDataEventArgs<Audit> e)
         {
+            if (!CurrentUser.IsAdmin()) return;
+
             var countLoad = await AuditService?.GetCount()!;
             if (countLoad.Success)
                 TotalAudits = countLoad.Data;

FoodsharingSiegen.Server/Shared/NavMenu.razor

@@ -64,7 +64,6 @@
                 </NavLink>
             </div>
         </div>
-    }
 
         <div class="nav-item px-3">
             <div @onclick="NavLinkClickedAsync">
@@ -73,6 +72,7 @@
                 </NavLink>
             </div>
         </div>
+    }
 
     <div class="flex-grow-1"></div>