Update .gitignore to exclude TypeScript build info and add dist directory. Expand README with project overview, technology stack, prerequisites, and instructions for running and testing the application.

src/HSchool.AppHost/AppHost.cs

@@ -0,0 +1,22 @@
+using Microsoft.Extensions.Configuration;
+
+var builder = DistributedApplication.CreateBuilder(args);
+
+var server = builder.AddProject<Projects.HSchool_Server>("server")
+    .WithHttpHealthCheck("/health")
+    .WithExternalHttpEndpoints();
+
+// Integration tests and CI run headless: no Node, no dev server, just the game server.
+var headless = builder.Configuration.GetValue("HSchool:Headless", false);
+
+if (!headless)
+{
+    var client = builder.AddViteApp("client", "../HSchool.Client")
+        .WithReference(server)
+        .WaitFor(server);
+
+    // On publish the built client is copied into the server image and served from wwwroot.
+    server.PublishWithContainerFiles(client, "wwwroot");
+}
+
+builder.Build().Run();