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.Server/Program.cs

@@ -0,0 +1,88 @@
+using System.Net.WebSockets;
+using HSchool.Server.Game;
+using HSchool.Server.Net;
+using HSchool.Simulation;
+
+var builder = WebApplication.CreateBuilder(args);
+
+builder.AddServiceDefaults();
+builder.Services.AddProblemDetails();
+builder.Services.AddOpenApi();
+
+builder.Services
+    .AddOptions<SimulationOptions>()
+    .Bind(builder.Configuration.GetSection(SimulationOptions.SectionName))
+    .Validate(options => options.TickRate is > 0 and <= 120, "Simulation:TickRate must be between 1 and 120.")
+    .Validate(options => options.WorldWidth > 0 && options.WorldHeight > 0, "World size must be positive.")
+    .ValidateOnStart();
+
+builder.Services.AddSingleton<GameCommandQueue>();
+builder.Services.AddSingleton<ClientRegistry>();
+builder.Services.AddSingleton<GameMetrics>();
+builder.Services.AddSingleton<GameSocketHandler>();
+builder.Services.AddSingleton<GameLoopService>();
+builder.Services.AddHostedService(sp => sp.GetRequiredService<GameLoopService>());
+
+builder.Services.AddOpenTelemetry().WithMetrics(metrics => metrics.AddMeter(GameMetrics.MeterName));
+
+var app = builder.Build();
+
+app.UseExceptionHandler();
+
+if (app.Environment.IsDevelopment())
+{
+    app.MapOpenApi();
+}
+
+app.UseWebSockets(new WebSocketOptions
+{
+    KeepAliveInterval = TimeSpan.FromSeconds(30),
+});
+
+var api = app.MapGroup("/api");
+
+api.MapGet("/status", (GameLoopService loop, ClientRegistry clients) =>
+{
+    var options = loop.Options;
+    return new GameStatusResponse(
+        loop.CurrentTick,
+        options.TickRate,
+        loop.PlayerCount,
+        clients.Count,
+        options.WorldWidth,
+        options.WorldHeight);
+})
+.WithName("GetGameStatus");
+
+// The realtime channel: one binary frame per protocol message, see docs/protocol.md.
+app.Map("/ws/game", async (HttpContext context, GameSocketHandler handler) =>
+{
+    if (!context.WebSockets.IsWebSocketRequest)
+    {
+        context.Response.StatusCode = StatusCodes.Status400BadRequest;
+        await context.Response.WriteAsync("This endpoint expects a WebSocket upgrade.");
+        return;
+    }
+
+    using WebSocket socket = await context.WebSockets.AcceptWebSocketAsync();
+    await handler.HandleAsync(socket, context.RequestAborted);
+});
+
+app.MapDefaultEndpoints();
+
+// In a published container the built client lands in wwwroot next to the server.
+app.UseFileServer();
+
+app.Run();
+
+/// <summary>Snapshot of loop health for dashboards and integration tests.</summary>
+internal sealed record GameStatusResponse(
+    uint Tick,
+    int TickRate,
+    int Players,
+    int Connections,
+    float WorldWidth,
+    float WorldHeight);
+
+/// <summary>Exposed so <c>WebApplicationFactory</c>-style tests can reference the entry point.</summary>
+public partial class Program;