Fix build and add tests (#6)

Template.Tests/StartupTest.cs

@@ -0,0 +1,40 @@
+using NUnit.Framework;
+using Robust.Client;
+using Robust.Shared.IoC;
+using Robust.UnitTesting;
+using Template.Game;
+
+namespace Template.Tests;
+
+[TestFixture]
+public sealed class StartupTest : RobustIntegrationTest
+{
+    [Test]
+    public async Task GameStartsSingleplayer()
+    {
+        var client = StartClient(new ClientIntegrationOptions
+        {
+            ContentStart = true,
+            ContentAssemblies = [typeof(EntryPoint).Assembly],
+            Options = new GameControllerOptions
+            {
+                ContentModulePrefix = "Template.",
+                ContentBuildDirectory = "Template.Game",
+                LoadConfigAndUserData = false,
+                LoadContentResources = false,
+            },
+        });
+
+        await client.WaitIdleAsync();
+
+        Assert.That(client.IsAlive, Is.True);
+        Assert.That(client.UnhandledException, Is.Null);
+
+        await client.WaitAssertion(() =>
+        {
+            var baseClient = IoCManager.Resolve<IBaseClient>();
+
+            Assert.That(baseClient.RunLevel, Is.EqualTo(ClientRunLevel.SinglePlayerGame));
+        });
+    }
+}

Template.Tests/Template.Tests.csproj

@@ -0,0 +1,24 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <Import Project="..\RobustToolbox\MSBuild\Robust.Properties.targets" />
+
+  <PropertyGroup>
+    <IsPackable>false</IsPackable>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+    <WarningsAsErrors>nullable</WarningsAsErrors>
+    <AppendTargetFrameworkToOutputPath>false</AppendTargetFrameworkToOutputPath>
+    <OutputPath>..\bin\Template.Tests\</OutputPath>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.NET.Test.Sdk" />
+    <PackageReference Include="NUnit" />
+    <PackageReference Include="NUnit3TestAdapter" />
+    <PackageReference Include="NUnit.Analyzers" PrivateAssets="All" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\Template.Game\Template.Game.csproj" />
+    <ProjectReference Include="..\RobustToolbox\Robust.UnitTesting\Robust.UnitTesting.csproj" />
+  </ItemGroup>
+</Project>