test(teleport): tp-probe AIM/ENQ/BUILD/APPLY/PLACED instrumentation (REMOVABLE)

Acceptance apparatus for the teleport-residency fix. ACDREAM_PROBE_TELEPORT=1
gates 5 log points with cross-thread TickCount64 timestamps + the _datLock
waited/held measurement. Stripped (or promoted) at verification (plan T6).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/AcDream.App/Rendering/GameWindow.cs

@@ -5472,6 +5472,9 @@ public sealed class GameWindow : IDisposable
             EnsureTeleportArrivalController();
             _pendingTeleportRot = rot;
             _teleportArrival!.BeginArrival(newWorldPos, p.LandblockId);
+            AcDream.Core.Physics.PhysicsDiagnostics.LogTeleport(
+                "AIM", p.LandblockId,
+                $"lb={lbX},{lbY} indoor={((p.LandblockId & 0xFFFFu) >= 0x0100u)} diffLb={differentLandblock}");
         }
     }
 
@@ -5561,6 +5564,8 @@ public sealed class GameWindow : IDisposable
             dt:                 1f / 60f);
 
         _playerController.State = AcDream.App.Input.PlayerState.InWorld;
+        AcDream.Core.Physics.PhysicsDiagnostics.LogTeleport(
+            "PLACED", resolved.CellId, $"forced={forced}");
         Console.WriteLine($"live: teleport complete — snapped to {snappedPos} cell=0x{resolved.CellId:X8}");
 
         // Tell the server the client finished loading the new landblock (holtburger
@@ -5813,6 +5818,25 @@ public sealed class GameWindow : IDisposable
         // case), which blocks the render thread for at most that duration.
         // This is the minimum correct behavior; a future pass can reduce
         // contention by pre-building render-thread work on the worker.
+        // tp-probe (2026-06-22, REMOVABLE): measure lock-WAIT (the _datLock
+        // contention signal — large only when the render thread is hammering the
+        // lock during a CreateObject flood) AND lock-HOLD (the intrinsic build
+        // cost). Identical work in both branches; the probe branch only adds the
+        // stopwatch + log. No behavior change when ProbeTeleportEnabled is false.
+        if (AcDream.Core.Physics.PhysicsDiagnostics.ProbeTeleportEnabled)
+        {
+            var sw = System.Diagnostics.Stopwatch.StartNew();
+            lock (_datLock)
+            {
+                long waitedMs = sw.ElapsedMilliseconds;
+                sw.Restart();
+                var built = BuildLandblockForStreamingLocked(landblockId, kind);
+                AcDream.Core.Physics.PhysicsDiagnostics.LogTeleport(
+                    "BUILD", landblockId,
+                    $"waited={waitedMs}ms held={sw.ElapsedMilliseconds}ms kind={kind}");
+                return built;
+            }
+        }
         lock (_datLock)
         {
             return BuildLandblockForStreamingLocked(landblockId, kind);
@@ -6414,6 +6438,7 @@ public sealed class GameWindow : IDisposable
         AcDream.Core.Terrain.LandblockMeshData meshData)
     {
         if (_terrain is null || _dats is null) return;
+        AcDream.Core.Physics.PhysicsDiagnostics.LogTeleport("APPLY", lb.LandblockId);
 
         // Phase A.1 hotfix: render-thread path also takes the dat lock so it
         // doesn't race with BuildLandblockForStreaming on the worker thread.

src/AcDream.App/Streaming/LandblockStreamer.cs

@@ -127,6 +127,7 @@ public sealed class LandblockStreamer : IDisposable
     {
         if (System.Threading.Volatile.Read(ref _disposed) != 0)
             throw new ObjectDisposedException(nameof(LandblockStreamer));
+        AcDream.Core.Physics.PhysicsDiagnostics.LogTeleport("ENQ", landblockId, $"kind={kind}");
         _inbox.Writer.TryWrite(new LandblockStreamJob.Load(landblockId, kind));
     }
 

src/AcDream.Core/Physics/PhysicsDiagnostics.cs

@@ -423,6 +423,31 @@ public static class PhysicsDiagnostics
     public static bool ProbeSweptEnabled { get; set; } =
         Environment.GetEnvironmentVariable("ACDREAM_PROBE_SWEPT") == "1";
 
+    /// <summary>
+    /// Teleport-foundation timing probe (2026-06-22 — REMOVABLE diagnostic).
+    /// Emits one <c>[tp-probe]</c> line per teleport-pipeline event with a
+    /// cross-thread monotonic timestamp (<see cref="Environment.TickCount64"/>)
+    /// so the offline reader can order AIM / ENQ / BUILD / APPLY / PLACED across
+    /// the render thread and the streamer worker. Disambiguates the three
+    /// candidate roots for "destination not resident fast": apply-THROTTLE
+    /// (APPLY lands before PLACED), <c>_datLock</c> CONTENTION (BUILD waited=
+    /// large), and a streaming-command GATE (ENQ never fires for the dest).
+    /// Initial state from <c>ACDREAM_PROBE_TELEPORT=1</c>. Strip after capture.
+    /// </summary>
+    public static bool ProbeTeleportEnabled { get; set; } =
+        Environment.GetEnvironmentVariable("ACDREAM_PROBE_TELEPORT") == "1";
+
+    /// <summary>
+    /// One <c>[tp-probe]</c> line. Self-guards on <see cref="ProbeTeleportEnabled"/>,
+    /// so callers need not pre-check (the cost when off is a single bool read).
+    /// </summary>
+    public static void LogTeleport(string point, uint id, string extra = "")
+    {
+        if (!ProbeTeleportEnabled) return;
+        Console.WriteLine(System.FormattableString.Invariant(
+            $"[tp-probe] {point,-6} id=0x{id:X8} t={Environment.TickCount64} {extra}"));
+    }
+
     /// <summary>
     /// A6.P3 issue #98 step-walk investigation (2026-05-23). When true,
     /// emits one <c>[step-walk]</c> line at selected points in the transition
@@ -549,6 +574,7 @@ public static class PhysicsDiagnostics
         ProbePlacementFailEnabled     = false;
         ProbeSweptEnabled             = false;
         ProbeStepWalkEnabled          = false;
+        ProbeTeleportEnabled          = false;
 
         // Side-channel fields
         LastBspHitPoly                = null;