feat: Update authentication and data seeding process

- Added default seeded users for the Sales API to facilitate login and avoid 401 errors during persistence.
- Modified DatabaseSeeder to ensure authentication data is seeded first, preventing access issues during subsequent data seeding.
- Enhanced customer and provider list components to handle null results gracefully, improving user experience and data loading reliability.

Author: Nieze-BenMansour

AUTH.md

@@ -100,6 +100,17 @@ public async Task<IResult> CreateInvoice(...) { }
 | `/api/auth/refresh` | POST | Refresh access token using refresh token |
 | `/api/auth/logout` | POST | Revoke refresh token |
 
+### Default seeded users (Sales API)
+
+After database seed (run at API startup), the following users exist. Use these to log in and avoid 401 when persisting.
+
+| Username | Password    | Role    |
+|----------|-------------|---------|
+| **admin** | **Admin123!** | Admin   |
+| Nieze    | Manager123! | Manager |
+
+Username is case-sensitive: use **admin** (lowercase), not Admin.
+
 ---
 
 ## Frontend (Blazor Server WebApp)

src/Modules/Sales/TunNetCom.SilkRoadErp.Sales.Api/Infrastructure/DataSeeder/DatabaseSeeder.cs

@@ -49,6 +49,9 @@ public async Task SeedAsync(SalesContext context)
                 }
             }
 
+            // Seed auth first so Admin user and roles exist before any other seed (avoids 401 when persisting)
+            await SeedAuthAsync(context);
+
             await SeedAccountingYearAsync(context);
             await SeedClientsAsync(context);
             await SeedFournisseursAsync(context);
@@ -58,7 +61,6 @@ public async Task SeedAsync(SalesContext context)
             await SeedProduitsAsync(context);
             await SeedBanquesAsync(context);
             await SeedInstallationTechniciansAsync(context);
-            await SeedAuthAsync(context);
 
             _logger.LogInformation("=== SEEDING DE LA BASE DE DONNÉES TERMINÉ AVEC SUCCÈS ===");
         }

src/Modules/Sales/TunNetCom.SilkRoadErp.Sales.WebApp/Components/Pages/Customers/CustomersList.razor

@@ -10,6 +10,7 @@
 @using TunNetCom.DeleteModal
 @using TunNetCom.SilkRoadErp.Sales.Contracts.Sorting
 @using TunNetCom.SilkRoadErp.Sales.WebApp.Components.Pages.Providers
+@using TunNetCom.SilkRoadErp.Sales.WebApp.Helpers
 @inject NavigationManager navigationManager
 @inject IStringLocalizer<SharedResource> Localizer
 @inject ICustomersApiClient customerService
@@ -214,20 +215,21 @@
 
     async Task LoadCustomerData(LoadDataArgs args)
     {
+        var paging = PaginationHelper.FromLoadDataArgs(args, _defaultPageSize);
 
         var parameters = new QueryStringParameters
             {
-                PageNumber = (args.Skip.Value / _defaultPageSize) + 1,
-                PageSize = args.Top ?? 10,
+                PageNumber = paging.PageNumber,
+                PageSize = paging.PageSize,
                 SearchKeyword = searchKeyword ?? args.Filter,
             };
 
         isLoadingCustomers = true;
         await Task.Yield();
 
         var result = await customerService.GetAsync(parameters, cancellationTokenSource.Token);
-        customers = result.Items;
-        totalCustomers = result.TotalCount;
+        customers = result?.Items ?? new List<CustomerResponse>();
+        totalCustomers = result?.TotalCount ?? 0;
 
         isLoadingCustomers = false;
         await InvokeAsync(StateHasChanged);

src/Modules/Sales/TunNetCom.SilkRoadErp.Sales.WebApp/Components/Pages/Providers/ProvidersList.razor

@@ -11,6 +11,7 @@
 @using TunNetCom.DeleteModal
 @using Microsoft.JSInterop
 @using System.Text.Json
+@using TunNetCom.SilkRoadErp.Sales.WebApp.Helpers
 
 @inject DialogService DialogService
 @inject IJSRuntime JSRuntime
@@ -234,16 +235,18 @@
 
     private async Task LoadData(LoadDataArgs args)
     {
+        var paging = PaginationHelper.FromLoadDataArgs(args, PageSize);
+
         var queryParameters = new QueryStringParameters
             {
-                PageNumber = (args.Skip ?? 0) / (args.Top ?? PageSize) + 1,
-                PageSize = args.Top ?? PageSize,
+                PageNumber = paging.PageNumber,
+                PageSize = paging.PageSize,
                 SearchKeyword = args.Filter
             };
 
         var result = await providerService.GetPagedAsync(queryParameters, cancellationTokenSource.Token);
-        providers = result.Items;
-        totalCount = result.TotalCount;
+        providers = result?.Items ?? new List<ProviderResponse>();
+        totalCount = result?.TotalCount ?? 0;
         await InvokeAsync(StateHasChanged);
     }
 
@@ -258,8 +261,8 @@
             };
 
         var result = await providerService.GetPagedAsync(queryParameters, cancellationTokenSource.Token);
-        providers = result.Items;
-        totalCount = result.TotalCount;
+        providers = result?.Items ?? new List<ProviderResponse>();
+        totalCount = result?.TotalCount ?? 0;
         await InvokeAsync(StateHasChanged);
     }
 

src/Modules/Sales/TunNetCom.SilkRoadErp.Sales.WebApp/Helpers/PaginationHelper.cs

@@ -0,0 +1,54 @@
+using Radzen;
+
+namespace TunNetCom.SilkRoadErp.Sales.WebApp.Helpers;
+
+/// <summary>
+/// Helper pour les calculs de pagination à partir de Radzen LoadDataArgs.
+/// </summary>
+public static class PaginationHelper
+{
+    /// <summary>
+    /// Retourne le nombre d'éléments à ignorer (skip), jamais null.
+    /// </summary>
+    public static int GetSafeSkip(LoadDataArgs args) => args.Skip ?? 0;
+
+    /// <summary>
+    /// Retourne la taille de page (top), toujours &gt; 0. Si args.Top est null ou 0, utilise defaultPageSize.
+    /// </summary>
+    public static int GetSafeTop(LoadDataArgs args, int defaultPageSize)
+    {
+        var top = args.Top ?? defaultPageSize;
+        return top > 0 ? top : defaultPageSize;
+    }
+
+    /// <summary>
+    /// Calcule le numéro de page (1-based) à partir de skip et top.
+    /// </summary>
+    public static int GetPageNumber(int skip, int top)
+    {
+        if (top <= 0) return 1;
+        return (skip / top) + 1;
+    }
+
+    /// <summary>
+    /// DTO pour les paramètres de pagination dérivés de LoadDataArgs.
+    /// </summary>
+    public readonly record struct PagingParams(int Skip, int Top, int PageNumber)
+    {
+        public int PageSize => Top;
+    }
+
+    /// <summary>
+    /// Extrait des paramètres de pagination sûrs à partir de LoadDataArgs.
+    /// </summary>
+    /// <param name="args">Arguments du RadzenDataGrid LoadData.</param>
+    /// <param name="defaultPageSize">Taille de page par défaut si args.Top est null ou 0.</param>
+    /// <returns>Skip, Top (toujours &gt; 0), et PageNumber (1-based).</returns>
+    public static PagingParams FromLoadDataArgs(LoadDataArgs args, int defaultPageSize)
+    {
+        var skip = GetSafeSkip(args);
+        var top = GetSafeTop(args, defaultPageSize);
+        var pageNumber = GetPageNumber(skip, top);
+        return new PagingParams(skip, top, pageNumber);
+    }
+}