refactor(app): complete session startup composition

Move the live-session reset and routing graph, combat and diagnostic command targets, and the sole gameplay input subscriber into Phase 7 before frame publication. Add exact retryable ownership for late bindings so partial startup cannot strand session or component teardown edges.

Co-authored-by: Codex <codex@openai.com>

tests/AcDream.App.Tests/Composition/InteractionUiRuntimeSourcesTests.cs

@@ -15,6 +15,23 @@ namespace AcDream.App.Tests.Composition;
 
 public sealed class InteractionUiRuntimeSourcesTests
 {
+    [Fact]
+    public void DesiredComponentSnapshotNormalizesNullAndClearsExactly()
+    {
+        var state = new DesiredComponentSnapshotState();
+        IReadOnlyList<(uint Id, uint Amount)> items =
+            [(0x01020304u, 7u)];
+
+        Assert.Empty(state.Items);
+        state.Items = items;
+        Assert.Same(items, state.Items);
+
+        state.Clear();
+        Assert.Empty(state.Items);
+        state.Items = null!;
+        Assert.Empty(state.Items);
+    }
+
     [Fact]
     public void SessionAuthorityDefaultsBindUnbindRebindAndDeactivateExactly()
     {

tests/AcDream.App.Tests/Composition/LivePresentationCompositionTests.cs

@@ -31,6 +31,24 @@ public sealed class LivePresentationCompositionTests
             bindings.Adopt("late", new RetryBinding("late", calls, 0)));
     }
 
+    [Fact]
+    public void TransferableAdoptionRollsBackExactlyAndRetriesFailure()
+    {
+        var calls = new List<string>();
+        var bindings = new LivePresentationRuntimeBindings();
+        bindings.Adopt("stable", new RetryBinding("stable", calls, 0));
+        IDisposable adoption = bindings.AdoptOwned(
+            "candidate",
+            new RetryBinding("candidate", calls, 1));
+
+        Assert.Throws<InvalidOperationException>(adoption.Dispose);
+        adoption.Dispose();
+        adoption.Dispose();
+        bindings.Dispose();
+
+        Assert.Equal(["candidate", "candidate", "stable"], calls);
+    }
+
     [Fact]
     public void CanonicalRuntimeSlotUsesExactOwnerBinding()
     {

tests/AcDream.App.Tests/Composition/SessionPlayerCompositionTests.cs

@@ -116,7 +116,19 @@ public sealed class SessionPlayerCompositionTests
             "new PlayerModeController(",
             "d.PortalTunnelFallback.Transfer(",
             "d.TeleportSink.BindOwned(localTeleport)",
+            "sessionRuntimeFactory.Create(liveSession)",
+            "d.CombatModeCommands.BindOwned(combatCommand)",
+            "d.RuntimeDiagnosticCommands.BindOwned(runtimeDiagnostics)",
+            "GameplayInputActionRouter.Create(",
+            "gameplayActions.Attach();",
             "_publication.PublishSessionPlayer(result);");
+
+        Assert.DoesNotContain("GameWindow", File.ReadAllText(Path.Combine(
+            FindRepoRoot(),
+            "src",
+            "AcDream.App",
+            "Net",
+            "LiveSessionRuntimeFactory.cs")), StringComparison.Ordinal);
     }
 
     private sealed class RetryBinding(