Adiciona suporte à autenticação Azure AD

Inclui a biblioteca `Microsoft.Identity.Client` em `SPOUser.cs` para autenticação via Azure AD. Cria a classe `SharePointAuthConfig` para gerenciar configurações de autenticação do SharePoint. Ajusta `UserConfig.xml` para manter as informações de autenticação e atualiza `packages.config` para incluir a nova biblioteca.

Author: kill74

SPOtoSQL-Snapshots/ConsoleApp1/Sharepoint/SPOUser.cs

@@ -1,4 +1,5 @@
 using Microsoft.SharePoint.Client;
+using Microsoft.Identity.Client;
 using System;
 using System.Security;
 

SPOtoSQL-Snapshots/ConsoleApp1/Sharepoint/SharePointAuthConfig.cs

@@ -0,0 +1,45 @@
+using System;
+
+namespace Bring.Sharepoint
+{
+    /// <summary>
+    /// Configuration class for SharePoint authentication methods
+    /// </summary>
+    public class SharePointAuthConfig
+    {
+        /// <summary>
+        /// Determines whether to use App Registration authentication
+        /// </summary>
+        public bool UseAppRegistration { get; set; }
+
+        /// <summary>
+        /// Azure AD Application (client) ID
+        /// </summary>
+        public string ClientId { get; set; }
+
+        /// <summary>
+        /// Azure AD Client Secret
+        /// </summary>
+        public string ClientSecret { get; set; }
+
+        /// <summary>
+        /// Azure AD Tenant ID
+        /// </summary>
+        public string TenantId { get; set; }
+
+        /// <summary>
+        /// SharePoint username for credential authentication
+        /// </summary>
+        public string Username { get; set; }
+
+        /// <summary>
+        /// SharePoint password for credential authentication
+        /// </summary>
+        public string Password { get; set; }
+
+        /// <summary>
+        /// SharePoint site URL
+        /// </summary>
+        public string SiteUrl { get; set; }
+    }
+}

SPOtoSQL-Snapshots/ConsoleApp1/packages.config

@@ -1,4 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
-  <package id="Microsoft.SharePointOnline.CSOM" version="16.1.19814.12000" targetFramework="net48" />
+	<package id="Microsoft.SharePointOnline.CSOM" version="16.1.19814.12000" targetFramework="net48" />
+	<package id="Microsoft.Identity.Client" version="4.55.0" targetFramework="net48" />
 </packages>