feat: implement VAT management service and integrate VAT calculations across components

src/FrontOffice.Main/Shared/MainLayout.razor

@@ -58,11 +58,11 @@
                 <div class="d-flex align-center gap-2">
                     @if (_isAuthenticated)
                     {
-                        <MudBadge Content="@_cartCount" Color="Color.Error" Overlap="true" Visible="@(_cartCount > 0)">
-                            <MudIconButton Icon="@Icons.Material.Filled.ShoppingCart" Color="Color.Inherit"
-                                           Href="@(RouteConstants.Store.Cart)" />
-                        </MudBadge>
-                        
+                        @* <MudBadge Content="@_cartCount" Color="Color.Error" Overlap="true" Visible="@(_cartCount > 0)"> *@
+                        @* *@
+                        @* </MudBadge> *@
+                        <MudIconButton Icon="@Icons.Material.Filled.ShoppingCart" Color="@(_cartCount > 0?Color.Success:Color.Inherit)"
+                                       Href="@(RouteConstants.Store.Cart)" />
                         <MudMenu Icon="@Icons.Material.Filled.Person" Color="Color.Inherit" Size="Size.Medium">
                             <MudMenuItem OnClick="NavigateToProfile" Disabled="@(!AuthService.IsCompleteRegister())">
                                 پروفایل

src/FrontOffice.Main/Shared/MainLayout.razor.cs

@@ -38,6 +38,8 @@ public partial class MainLayout : IDisposable
             
             if (_isAuthenticated)
             {
+                // لود سبد خرید فقط برای کاربر لاگین شده
+                await CartService.EnsureInitializedAsync();
                 CartService.OnChange += OnCartChanged;
                 _cartCount = CartService.Count;
             }