feat(launcher): complete Campaign LA11 pre-gate support

tests/AcDream.Launcher.Tests/LauncherUpdateCompositionTests.cs

@@ -62,4 +62,44 @@ public sealed class LauncherUpdateCompositionTests : IDisposable
             () => composition.Updater.CheckAsync());
         Assert.Contains(exception.Message, updateError.Message, StringComparison.Ordinal);
     }
+
+    [Theory]
+    [InlineData("https://updates.example.test/manifest.json")]
+    [InlineData("http://127.0.0.1:43119/manifest.json")]
+    public void ProcessLocalManifestOverrideReachesOnlyUpdateComposition(string value)
+    {
+        Directory.CreateDirectory(_root);
+        var paths = new ApplicationPathSet(
+            Path.Combine(_root, "config"),
+            Path.Combine(_root, "data"),
+            Path.Combine(_root, "cache"),
+            null);
+        var manifestUri = new Uri(value);
+
+        using LauncherUpdateComposition composition = LauncherUpdateComposition.Create(
+            paths,
+            LauncherRuntimeIdentity.DetectRid(),
+            LauncherVersion.Parse("1.0.0"),
+            _root,
+            () => false,
+            initialize: (_, _) => new ClientVersionResolution(
+                ClientVersionState.Missing,
+                "No client version is installed.",
+                null,
+                null,
+                null,
+                null),
+            updateManifestUri: manifestUri);
+
+        Assert.Same(manifestUri, composition.UpdateManifestUri);
+        Assert.Equal(
+            Path.Combine(paths.DataDirectory, "app"),
+            composition.Versions.AppDirectory);
+        Assert.False(File.Exists(
+            Path.Combine(paths.ConfigDirectory, "launcher-profiles.json")));
+        Assert.Empty(Directory.EnumerateFiles(
+            _root,
+            "*",
+            SearchOption.AllDirectories));
+    }
 }