refactor(runtime): extract local teleport and player mode

Move local teleport, player-mode, animation, shadow, and sealed-dungeon lifetimes out of GameWindow. Make player-mode entry transactional and isolate approach completions by controller lifetime and approach generation so stale callbacks cannot affect replacements.

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

tests/AcDream.App.Tests/Interaction/PlayerApproachCompletionStateTests.cs

@@ -0,0 +1,79 @@
+using AcDream.App.Interaction;
+using AcDream.Core.Physics;
+
+namespace AcDream.App.Tests.Interaction;
+
+public sealed class PlayerApproachCompletionStateTests
+{
+    [Fact]
+    public void CompletionMailbox_PreservesPublicationOrder()
+    {
+        var state = new PlayerApproachCompletionState();
+        IPlayerApproachCompletionSink lifetime = state.BeginControllerLifetime();
+
+        Assert.True(state.TryBeginApproach(out PlayerApproachToken token));
+        lifetime.PublishNaturalCompletion();
+        lifetime.PublishCancellation(WeenieError.NoObject);
+
+        Assert.True(state.TryTake(out PlayerApproachCompletion natural));
+        Assert.Equal(token, natural.Token);
+        Assert.True(natural.IsNatural);
+        Assert.Equal(WeenieError.None, natural.Error);
+        Assert.True(state.TryTake(out PlayerApproachCompletion cancellation));
+        Assert.False(cancellation.IsNatural);
+        Assert.Equal(WeenieError.NoObject, cancellation.Error);
+        Assert.False(state.TryTake(out _));
+    }
+
+    [Fact]
+    public void Clear_DiscardsEveryPendingCompletion()
+    {
+        var state = new PlayerApproachCompletionState();
+        IPlayerApproachCompletionSink lifetime = state.BeginControllerLifetime();
+        Assert.True(state.TryBeginApproach(out _));
+        lifetime.PublishNaturalCompletion();
+        lifetime.PublishCancellation(WeenieError.ActionCancelled);
+
+        state.Clear();
+
+        Assert.False(state.TryTake(out _));
+    }
+
+    [Fact]
+    public void RetiredLifetime_CannotPublishIntoReplacementLifetime()
+    {
+        var state = new PlayerApproachCompletionState();
+        IPlayerApproachCompletionSink stale = state.BeginControllerLifetime();
+        Assert.True(state.TryBeginApproach(out PlayerApproachToken staleToken));
+        state.RetireControllerLifetime(stale);
+        Assert.True(state.TryTake(out PlayerApproachCompletion retirement));
+        Assert.Equal(staleToken, retirement.Token);
+        Assert.False(retirement.IsNatural);
+        IPlayerApproachCompletionSink current = state.BeginControllerLifetime();
+        Assert.True(state.TryBeginApproach(out PlayerApproachToken currentToken));
+
+        stale.PublishNaturalCompletion();
+        current.PublishNaturalCompletion();
+
+        Assert.True(state.TryTake(out PlayerApproachCompletion completion));
+        Assert.Equal(currentToken, completion.Token);
+        Assert.False(state.TryTake(out _));
+    }
+
+    [Fact]
+    public void Retirement_ReplacesQueuedSuccessWithMatchingCancellation()
+    {
+        var state = new PlayerApproachCompletionState();
+        IPlayerApproachCompletionSink lifetime = state.BeginControllerLifetime();
+        Assert.True(state.TryBeginApproach(out PlayerApproachToken token));
+        lifetime.PublishNaturalCompletion();
+
+        state.RetireControllerLifetime(lifetime);
+
+        Assert.True(state.TryTake(out PlayerApproachCompletion completion));
+        Assert.Equal(token, completion.Token);
+        Assert.False(completion.IsNatural);
+        Assert.Equal(WeenieError.ActionCancelled, completion.Error);
+        Assert.False(state.TryTake(out _));
+    }
+}