添加项目文件。

Program.cs

@@ -0,0 +1,50 @@
+using AcdiuTools.Services;
+
+var builder = WebApplication.CreateBuilder(args);
+
+// 1. 添加 MVC 控制器支持
+builder.Services.AddControllersWithViews();
+
+// 2. 注册 HttpContextAccessor (之前已添加，确保存在)
+builder.Services.AddHttpContextAccessor();
+
+// 3. 注册 Session 服务
+// AddSession 必须放在 AddControllersWithViews 之后或之前均可，但必须在 Build 之前
+builder.Services.AddSession(options =>
+{
+    options.IdleTimeout = TimeSpan.FromMinutes(30); // Session 过期时间
+    options.Cookie.HttpOnly = true;
+    options.Cookie.IsEssential = true; // 即使未同意 Cookie 策略也发送（用于功能必需）
+});
+
+// 注册主题服务
+builder.Services.AddScoped<IThemeService, ThemeService>();
+
+var app = builder.Build();
+
+// 4. 配置中间件管道
+// UseSession 必须放在 UseRouting 之后，UseAuthorization 和 MapControllers 之前
+if (!app.Environment.IsDevelopment())
+{
+    app.UseExceptionHandler("/Home/Error");
+    // The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.
+    app.UseHsts();
+}
+
+app.UseHttpsRedirection();
+app.UseRouting();
+
+// 【关键】启用 Session 中间件
+app.UseSession();
+
+app.UseAuthorization();
+
+app.MapStaticAssets();
+
+app.MapControllerRoute(
+    name: "default",
+    pattern: "{controller=Home}/{action=Index}/{id?}")
+    .WithStaticAssets();
+
+
+app.Run();