docs(vfx #C.1.5a): implementation plan + spec wiring-location fixes

Plan: docs/superpowers/plans/2026-05-12-phase-c1.5a-portals.md. Four
tasks, TDD-style, each task is a single commit boundary:
  1. EntityScriptActivator class + three xUnit tests
  2. Wire into GpuWorldState (new optional ctor param + two ?. calls)
  3. Construct in GameWindow with resolver lambda
  4. Visual verification at Holtburg Town network portal + roadmap update

Spec amendments correct an inaccuracy in the 2026-05-12 commit
(06d7fbd): the activator's call sites live in GpuWorldState
(AppendLiveEntity / RemoveEntityByServerGuid), not directly in
GameWindow as the original spec described. Also fixes the test file
path: tests/AcDream.Core.Tests/... not AcDream.App.Tests/... per the
existing test-project convention. No design changes — same activator,
same trigger condition, same lifecycle ordering.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

docs/superpowers/specs/2026-05-12-phase-c1.5a-portals-design.md

@@ -25,9 +25,12 @@ swirl matches retail in color, density, motion, and persistence.
 **In:**
 
 - New class `EntityScriptActivator` (one file, ~50 lines).
-- Wiring of activator's `OnCreate` / `OnRemove` calls into `GameWindow`'s
-  spawn-lifecycle handlers, immediately after the matching `EntitySpawnAdapter`
-  calls.
+- Wiring of activator's `OnCreate` / `OnRemove` calls into `GpuWorldState`'s
+  spawn-lifecycle methods (`AppendLiveEntity` / `RemoveEntityByServerGuid`),
+  immediately after the matching `EntitySpawnAdapter` calls. The activator is
+  constructed in `GameWindow` (where `_dats`, `_scriptRunner`, and
+  `_particleSink` are in scope) and passed into `GpuWorldState`'s constructor
+  as a new optional parameter, paralleling how `EntitySpawnAdapter` is wired.
 - Three unit tests covering the activator's three branches
   (fire / no-op-on-zero / cleanup-on-remove).
 - Visual verification at the Holtburg Town network portal.
@@ -145,18 +148,32 @@ data faithfully and the visual is what retail shows. If retail does NOT show
 those particles and we do, that's evidence of a different gate retail
 applies — to be investigated when seen.
 
-### Wiring point: GameWindow
+### Wiring point: GpuWorldState
+
+Live entity spawn / despawn already flows through
+[`GpuWorldState`](../../../src/AcDream.App/Streaming/GpuWorldState.cs) on the
+render thread — the network layer pushes spawns into
+`AppendLiveEntity(landblockId, entity)`, the server's `RemoveObject` opcode
+routes through `RemoveEntityByServerGuid(serverGuid)`. The existing
+`EntitySpawnAdapter` lifecycle hooks live at those two call sites
+(line 345 `OnCreate`, line 285 `OnRemove`). The activator hooks fire
+immediately after, in the same order:
 
 ```csharp
-// In GameWindow.OnCreateObject(WorldEntity entity):
-_entitySpawnAdapter.OnCreate(entity);
-_entityScriptActivator.OnCreate(entity);   // NEW — runs after meshes are registered
+// GpuWorldState.AppendLiveEntity (line ~345):
+_wbEntitySpawnAdapter?.OnCreate(entity);
+_entityScriptActivator?.OnCreate(entity);   // NEW — fires DefaultScript
 
-// In GameWindow.OnRemoveObject(uint serverGuid):
-_entitySpawnAdapter.OnRemove(serverGuid);
-_entityScriptActivator.OnRemove(serverGuid);   // NEW — runs in same order as create
+// GpuWorldState.RemoveEntityByServerGuid (line ~285):
+_wbEntitySpawnAdapter?.OnRemove(serverGuid);
+_entityScriptActivator?.OnRemove(serverGuid);   // NEW — stops scripts + emitters
 ```
 
+`GpuWorldState`'s constructor grows a fifth (optional) parameter for the
+activator, paralleling how `EntitySpawnAdapter` is plumbed today. `GameWindow`
+constructs the activator alongside `_wbEntitySpawnAdapter` and passes it
+through.
+
 Production resolver lambda, constructed in `GameWindow` where `_dats` is in
 scope:
 
@@ -183,9 +200,9 @@ The try/catch matches the pattern in
 ### On spawn
 
 ```
-GameWindow.OnCreateObject(entity)
-├─ _entitySpawnAdapter.OnCreate(entity)        // meshes ref-counted, animation state built
-└─ _entityScriptActivator.OnCreate(entity)
+GpuWorldState.AppendLiveEntity(landblockId, entity)
+├─ _wbEntitySpawnAdapter?.OnCreate(entity)     // meshes ref-counted, animation state built
+└─ _entityScriptActivator?.OnCreate(entity)
    ├─ scriptId = resolver(entity)              // Setup.DefaultScript.DataId, or 0 on miss/throw
    ├─ if (scriptId == 0) return                // no DefaultScript → no-op
    └─ _scriptRunner.Play(scriptId,
@@ -199,9 +216,9 @@ GameWindow.OnCreateObject(entity)
 ### On despawn
 
 ```
-GameWindow.OnRemoveObject(serverGuid)
-├─ _entitySpawnAdapter.OnRemove(serverGuid)            // meshes ref-decremented, state cleared
-└─ _entityScriptActivator.OnRemove(serverGuid)
+GpuWorldState.RemoveEntityByServerGuid(serverGuid)
+├─ _wbEntitySpawnAdapter?.OnRemove(serverGuid)         // meshes ref-decremented, state cleared
+└─ _entityScriptActivator?.OnRemove(serverGuid)
    ├─ _scriptRunner.StopAllForEntity(serverGuid)       // drop pending hooks
    └─ _particleSink.StopAllForEntity(serverGuid, false) // kill live emitters (no fade)
 ```
@@ -270,7 +287,11 @@ new threading concerns introduced.
 
 ### Unit tests (slice 1's gating tests)
 
-`tests/AcDream.App.Tests/Rendering/Vfx/EntityScriptActivatorTests.cs`. Uses
+`tests/AcDream.Core.Tests/Rendering/Vfx/EntityScriptActivatorTests.cs` (test
+project convention: production code lives under `src/AcDream.App/...` but tests
+go in `AcDream.Core.Tests` — mirrors the existing
+[`EntitySpawnAdapterTests`](../../../tests/AcDream.Core.Tests/Rendering/Wb/EntitySpawnAdapterTests.cs)
+location). Uses
 hand-built `PhysicsScriptRunner` + capturing `ParticleHookSink` (or a thin
 test double). No dats, no GL.
 
@@ -286,9 +307,11 @@ test double). No dats, no GL.
 
 ### Integration tests — none for slice 1
 
-The `GameWindow` wiring is two added lines (one in `OnCreateObject`, one in
-`OnRemoveObject`). An integration test would require booting GL + dats +
-network. Coverage is the visual verification gate instead.
+The `GpuWorldState` wiring is two added lines (one in `AppendLiveEntity`, one
+in `RemoveEntityByServerGuid`) plus a constructor parameter. An integration
+test would require booting GL + dats + network. Coverage is the visual
+verification gate instead. Existing `GpuWorldStateTests` will need a minor
+update if they assert constructor arity; we extend them if so.
 
 ### Visual verification — the acceptance criterion