Split viewer and simulation into separate apps

apps/backend/Program.cs

@@ -0,0 +1,36 @@
+using SpaceGame.Simulation.Api.Simulation;
+
+var builder = WebApplication.CreateBuilder(args);
+
+builder.WebHost.UseUrls("http://127.0.0.1:5079");
+builder.Services.AddCors((options) =>
+{
+  options.AddDefaultPolicy((policy) =>
+  {
+    policy
+      .AllowAnyHeader()
+      .AllowAnyMethod()
+      .AllowAnyOrigin();
+  });
+});
+builder.Services.AddSingleton<WorldService>();
+builder.Services.AddHostedService<SimulationHostedService>();
+
+var app = builder.Build();
+
+app.UseCors();
+
+app.MapGet("/", () => Results.Redirect("/api/world"));
+app.MapGet("/api/world", (WorldService worldService) => Results.Ok(worldService.GetSnapshot()));
+app.MapGet("/api/world/health", (WorldService worldService) => Results.Ok(new
+{
+  ok = true,
+  generatedAtUtc = worldService.GetSnapshot().GeneratedAtUtc,
+}));
+app.MapPost("/api/world/reset", (WorldService worldService) =>
+{
+  var snapshot = worldService.Reset();
+  return Results.Ok(snapshot);
+});
+
+app.Run();