Reorganize tests by API and service concerns

RpgRoller.Tests/HostingCoverageTests.cs

@@ -0,0 +1,30 @@
+using Microsoft.Extensions.Configuration;
+using Microsoft.Extensions.DependencyInjection;
+using RpgRoller.Hosting;
+
+namespace RpgRoller.Tests;
+
+public sealed class HostingCoverageTests
+{
+    [Fact]
+    public void AddRpgRollerCore_WithInMemoryConnectionString_RegistersCoreServices()
+    {
+        var services = new ServiceCollection();
+        var configuration = new ConfigurationBuilder()
+            .AddInMemoryCollection(new Dictionary<string, string?>
+            {
+                ["ConnectionStrings:RpgRoller"] = "Data Source=:memory:"
+            })
+            .Build();
+
+        var environment = new TestWebHostEnvironment
+        {
+            ContentRootPath = Path.GetTempPath()
+        };
+
+        services.AddRpgRollerCore(configuration, environment);
+
+        Assert.Contains(services, d => d.ServiceType == typeof(RpgRoller.Services.IGameService));
+        Assert.Contains(services, d => d.ServiceType == typeof(RpgRoller.Services.IDiceRoller));
+    }
+}