Fix admin client and auth flows

src/TaxBaik.Web.Client/Components/Admin/Pages/Clients/ClientEdit.razor

@@ -1,6 +1,6 @@
 @page "/admin/clients/create"
 @page "/admin/clients/{Id:int}/edit"
-@rendermode @(new InteractiveWebAssemblyRenderMode(prerender: true))
+@rendermode @(new InteractiveWebAssemblyRenderMode(prerender: false))
 @attribute [Authorize]
 @using TaxBaik.Application.DTOs
 @using TaxBaik.Web.Services
@@ -74,7 +74,7 @@
                 </MudItem>
                 <MudItem xs="12">
                     <MudTextField @bind-Value="dto.Memo" Label="메모"
-                                  Lines="4" AutoGrow="true"
+                                  Lines="4"
                                   Placeholder="상담 배경, 특이사항, 중요 날짜 등 자유롭게 기록하세요" />
                 </MudItem>
 
@@ -148,7 +148,7 @@
 
     private async Task SaveAsync()
     {
-        await form.Validate();
+        await form.ValidateAsync();
         if (!isValid) return;
 
         isSaving = true;