fix(streaming): #138-B avatar vanishes after teleporting out — don't relocate during PortalSpace

After a teleport-OUT the per-frame avatar-sync (GameWindow ~:8018) called
GpuWorldState.RelocateEntity with the player controller's cell — which stays the
FROZEN SOURCE cell until PlaceTeleportArrival materializes the destination. So
mid-transit it dragged the avatar (which the teleport's rescue/re-inject had
correctly placed at the destination center) back into the now-UNLOADED source
landblock's pending bucket, where nothing recovers it (RelocateEntity only scans
_loaded). Net: the avatar vanished after teleporting out and stayed gone.

Fix: skip the per-frame relocate while the player is in PortalSpace. The teleport
machinery (DrainRescued + PlaceTeleportArrival) owns the avatar's landblock during
transit; per-frame relocation resumes at FireLoginComplete (InWorld).

Live-verified with a new env-gated avatar-lifecycle probe (ACDREAM_PROBE_ENT /
EntityVanishProbe; [ent] draw-set transitions + [dyn] cull check): pre-fix the
trace showed `[ent] APPEND lb=0x0007FFFF(source) -> PENDING -> DRAWSET ABSENT`
never recovering; post-fix every teleport goes RESCUE -> ABSENT ->
APPEND(destination) -> PRESENT and stays drawn (4 teleports incl. to Holtburg,
session ended PRESENT).

Suites green: Core 1568(+2 skip), App 468(+2 skip), UI 425, Net 317.

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

src/AcDream.App/Streaming/EntityVanishProbe.cs

@@ -0,0 +1,49 @@
+using System;
+
+namespace AcDream.App.Streaming;
+
+/// <summary>
+/// TEMP diagnostic (#138-B avatar-vanish). Env-gated (<c>ACDREAM_PROBE_ENT=1</c>)
+/// trace of the persistent player entity across teleport streaming churn:
+/// whether it is present in the render draw-DATA (<see cref="GpuWorldState"/>
+/// flat view) and whether it survives the dynamics CULL
+/// (<c>RetailPViewRenderer.DrawDynamicsLast</c>).
+///
+/// <para>The two halves answer the decisive question: is the avatar
+/// "missing for a moment" because it is <b>absent from the draw set</b>
+/// (re-injected into the pending bucket while its landblock re-streams), or
+/// because it is <b>present but culled</b> (in the dynamics list, dropped by
+/// the outside-stage / viewcone gate)?</para>
+///
+/// <para>STRIP once #138-B is root-caused (throwaway, like the dense-town FPS
+/// apparatus). Observation-only — emits no behavior change.</para>
+/// </summary>
+internal static class EntityVanishProbe
+{
+    public static readonly bool Enabled =
+        Environment.GetEnvironmentVariable("ACDREAM_PROBE_ENT") == "1";
+
+    /// <summary>Player server guid, set once at world entry so the draw-side
+    /// <c>[dyn]</c> line can single out the avatar without plumbing the guid
+    /// through the render stack.</summary>
+    public static uint PlayerGuid;
+
+    public static void Log(string msg)
+    {
+        if (Enabled) Console.WriteLine(msg);
+    }
+
+    private static string _lastPlayerDyn = "";
+
+    /// <summary>Emit a <c>[dyn] player</c> line only when the outcome string
+    /// changes — a stationary, drawn avatar must not spam one line per frame
+    /// (that console+Tee I/O would itself depress FPS and bury the signal).
+    /// Fires on cell change or DRAWN↔CULLED transition.</summary>
+    public static void LogPlayerDynOnChange(string status)
+    {
+        if (!Enabled) return;
+        if (status == _lastPlayerDyn) return;
+        _lastPlayerDyn = status;
+        Console.WriteLine("[dyn] player " + status);
+    }
+}

src/AcDream.App/Streaming/GpuWorldState.cs

@@ -298,6 +298,7 @@ public sealed class GpuWorldState
                 if (entity.ServerGuid != 0 && _persistentGuids.Contains(entity.ServerGuid))
                 {
                     _persistentRescued.Add(entity);
+                    EntityVanishProbe.Log($"[ent] RESCUE guid=0x{entity.ServerGuid:X8} from=loaded lb=0x{landblockId:X8}");
                 }
             }
 
@@ -331,7 +332,10 @@ public sealed class GpuWorldState
             foreach (var entity in pendingForLb)
             {
                 if (entity.ServerGuid != 0 && _persistentGuids.Contains(entity.ServerGuid))
+                {
                     _persistentRescued.Add(entity);
+                    EntityVanishProbe.Log($"[ent] RESCUE guid=0x{entity.ServerGuid:X8} from=pending lb=0x{landblockId:X8}");
+                }
             }
         }
 
@@ -439,6 +443,8 @@ public sealed class GpuWorldState
         _entityScriptActivator?.OnCreate(entity);
 
         uint canonicalLandblockId = (landblockId & 0xFFFF0000u) | 0xFFFFu;
+        bool probePersistent = EntityVanishProbe.Enabled
+            && entity.ServerGuid != 0 && _persistentGuids.Contains(entity.ServerGuid);
 
         if (_loaded.TryGetValue(canonicalLandblockId, out var lb))
         {
@@ -451,6 +457,8 @@ public sealed class GpuWorldState
                 lb.LandblockId,
                 lb.Heightmap,
                 newEntities);
+            if (probePersistent)
+                EntityVanishProbe.Log($"[ent] APPEND guid=0x{entity.ServerGuid:X8} lb=0x{canonicalLandblockId:X8} -> LOADED(drawn)");
             RebuildFlatView();
             return;
         }
@@ -464,6 +472,8 @@ public sealed class GpuWorldState
             _pendingByLandblock[canonicalLandblockId] = bucket;
         }
         bucket.Add(entity);
+        if (probePersistent)
+            EntityVanishProbe.Log($"[ent] APPEND guid=0x{entity.ServerGuid:X8} lb=0x{canonicalLandblockId:X8} -> PENDING(hidden)");
     }
 
     /// <summary>
@@ -570,5 +580,29 @@ public sealed class GpuWorldState
     private void RebuildFlatView()
     {
         _flatEntities = _loaded.Values.SelectMany(lb => lb.Entities).ToArray();
+        if (EntityVanishProbe.Enabled) ProbeFlatViewTransitions();
+    }
+
+    // TEMP (#138-B): persistent guids currently present in the drawn flat
+    // view, for EntityVanishProbe transition logging. Strip with the probe.
+    private readonly HashSet<uint> _persistentInFlatProbe = new();
+
+    // TEMP (#138-B): log when a persistent (player) entity enters/leaves the
+    // drawn flat view. Transition-gated → low volume (fires at teleport
+    // boundaries, not every rebuild). Strip with EntityVanishProbe.
+    private void ProbeFlatViewTransitions()
+    {
+        var now = new HashSet<uint>();
+        foreach (var e in _flatEntities)
+            if (e.ServerGuid != 0 && _persistentGuids.Contains(e.ServerGuid))
+                now.Add(e.ServerGuid);
+        foreach (var g in now)
+            if (!_persistentInFlatProbe.Contains(g))
+                EntityVanishProbe.Log($"[ent] DRAWSET guid=0x{g:X8} -> PRESENT (flatCount={_flatEntities.Count})");
+        foreach (var g in _persistentInFlatProbe)
+            if (!now.Contains(g))
+                EntityVanishProbe.Log($"[ent] DRAWSET guid=0x{g:X8} -> ABSENT (flatCount={_flatEntities.Count})");
+        _persistentInFlatProbe.Clear();
+        foreach (var g in now) _persistentInFlatProbe.Add(g);
     }
 }