Fix admin client and auth flows

src/TaxBaik.Web.Client/Components/Admin/Pages/Announcements/AnnouncementEdit.razor

@@ -1,6 +1,6 @@
 @page "/admin/announcements/create"
 @page "/admin/announcements/{Id:int}/edit"
-@rendermode @(new InteractiveWebAssemblyRenderMode(prerender: true))
+@rendermode @(new InteractiveWebAssemblyRenderMode(prerender: false))
 @attribute [Authorize]
 @using System.ComponentModel.DataAnnotations
 @using TaxBaik.Application.DTOs
@@ -70,7 +70,7 @@
             </MudItem>
 
             <MudItem xs="12">
-                <MudSwitch @bind-Checked="model.IsActive"
+                <MudSwitch T="bool" @bind-Value="model.IsActive"
                            Label="@(model.IsActive ? "활성화 (홈페이지에 노출)" : "비활성화 (홈페이지 미노출)")"
                            Color="Color.Primary" />
             </MudItem>
@@ -135,7 +135,7 @@
     private async Task SaveAsync()
     {
         if (form is null) return;
-        await form.Validate();
+        await form.ValidateAsync();
         if (!form.IsValid) return;
 
         isSaving = true;