Initial project setup: solution + 5 projects

- Domain, Infrastructure, Application (class libraries)
- Web (ASP.NET Core empty)
- Admin (Blazor Server)
- All net8.0 target framework
- Project references configured

Co-Authored-By: Claude <noreply@anthropic.com>

TaxBaik.Admin/Program.cs

@@ -0,0 +1,31 @@
+using Microsoft.AspNetCore.Components;
+using Microsoft.AspNetCore.Components.Web;
+using TaxBaik.Admin.Data;
+
+var builder = WebApplication.CreateBuilder(args);
+
+// Add services to the container.
+builder.Services.AddRazorPages();
+builder.Services.AddServerSideBlazor();
+builder.Services.AddSingleton<WeatherForecastService>();
+
+var app = builder.Build();
+
+// Configure the HTTP request pipeline.
+if (!app.Environment.IsDevelopment())
+{
+    app.UseExceptionHandler("/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.UseStaticFiles();
+
+app.UseRouting();
+
+app.MapBlazorHub();
+app.MapFallbackToPage("/_Host");
+
+app.Run();