feat(render): Phase A8 — indoor visibility + streaming fixes batch

Lands the working A8 indoor-rendering and streaming fixes accumulated this
session. User has verified these visually to some degree (e.g. lifestone /
translucent meshes confirmed fine under the FrontFace flip; bridge / wall /
collision regressions confirmed fixed after travel); not every path has been
exhaustively gated. The cellar-flap defect remains OPEN and will be solved
the retail-faithful way via a dedicated brainstorm (see handoff docs).

Rendering core (reviewed, high confidence):
- EnvCellRenderer SSBO stride fix: upload packed Matrix4x4[] (64B) instead of
  the 80B CPU InstanceData struct the shader never expected — fixes the
  transform/texture "explosion" for any draw with >1 instance (cells that
  dedupe to a shared cellGeomId). Real root cause.
- WB-style global FrontFace(CW) + per-batch CullMode carried through the MDI
  layout (GroupKey + BuildIndirectArrays + DrawIndirectRange split into
  same-cull runs with absolute uDrawIDOffset per run).
- EntitySet partitioning (IndoorPass / OutdoorScenery / LiveDynamic) +
  WorldEntity.BuildingShellAnchorCellId so building shells scope to their
  dat-derived building cell instead of rendering everywhere.
- RenderOutsideInAcdream (look into buildings from outside) +
  CollectVisiblePortalBuildings frustum cull of portal bounds.
- Sky-when-inside-building + per-cell audit probe + GL-state probe.

Streaming / perf (test-covered; not independently code-reviewed this session):
- Near/far priority queues so near work wins over far; PromoteToNear carries
  full landblock + mesh data; LandblockEntriesWithoutAnimatedIndex avoids
  rebuilding the animated-lookup dict in the hot draw path. Fixes the
  bridge-not-appearing / missing-walls / broken-collision-after-travel
  regressions and improves post-transition FPS.

Tooling + docs:
- tools/A8CellAudit: offline dat cell/portal/building dumper (portals +
  buildings modes) — reproduces the cellar-flap investigation with no launch.
- docs/research cellar-flap root-cause + option-2 handoff (the didInsideStencil
  double-duty finding + the WB-recursive design decision + brainstorm prompt),
  entity-taxonomy, replan, issue-78 visibility investigation.

Diagnostics retained on purpose: ACDREAM_A8_DIAG_* gates, portal_stencil.vert
provisional pos.w clamp, and the probe families are kept (env-var gated, zero
cost when off) because the pending option-2 cellar-flap brainstorm needs them.
Strip in the option-2 ship commit.

Indoor branch stays behind ACDREAM_A8_INDOOR_BRANCH=1 (default off = pre-A8
visual). Build green; App tests + Core (streaming/dispatcher/loader) tests pass.

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

tests/AcDream.Core.Tests/Rendering/Wb/WbDrawDispatcherCellIdsOverloadTests.cs

@@ -2,7 +2,8 @@
 // the pure-data companion to the new Draw(cellIds:) production overload.
 //
 // Semantics: indoor entities (ParentCellId.HasValue) are gated by explicit
-// membership in cellIds. Building shells (IsBuildingShell) always pass.
+// membership in cellIds. Building shells (IsBuildingShell) pass only when their
+// BuildingShellAnchorCellId belongs to the same cell set.
 // Outdoor scenery (no ParentCellId, not a shell) is excluded by EntitySet.IndoorPass.
 
 using System.Collections.Generic;
@@ -36,12 +37,13 @@ public class WbDrawDispatcherCellIdsOverloadTests
         Rotation = Quaternion.Identity,
     };
 
-    private static WorldEntity BuildingShell(uint id) => new()
+    private static WorldEntity BuildingShell(uint id, uint? anchorCellId) => new()
     {
         Id = id,
         SourceGfxObjOrSetupId = 0x02000001u,
         ParentCellId = null,
         IsBuildingShell = true,
+        BuildingShellAnchorCellId = anchorCellId,
         MeshRefs = new List<MeshRef> { new(0x01000001u, Matrix4x4.Identity) },
         Position = Vector3.Zero,
         Rotation = Quaternion.Identity,
@@ -55,7 +57,8 @@ public class WbDrawDispatcherCellIdsOverloadTests
             CellEnt(0x40000001u, 0xA9B40150u),  // in listed cells
             CellEnt(0x40000002u, 0xA9B40151u),  // in listed cells
             CellEnt(0x40000003u, 0xA9B40999u),  // OUT — not in list
-            BuildingShell(0xC0000001u),          // always included (IsBuildingShell)
+            BuildingShell(0xC0000001u, 0xA9B40150u), // in listed building cells
+            BuildingShell(0xC0000003u, 0xA9B40999u), // OUT — another building shell
             OutdoorScenery(0xC0000002u),         // OUT — not a shell, not in cell list
         };
         var cellIds = new HashSet<uint> { 0xA9B40150u, 0xA9B40151u };
@@ -68,23 +71,22 @@ public class WbDrawDispatcherCellIdsOverloadTests
         Assert.Contains(0x40000002u, result);
         Assert.Contains(0xC0000001u, result);
         Assert.DoesNotContain(0x40000003u, result);
+        Assert.DoesNotContain(0xC0000003u, result);
         Assert.DoesNotContain(0xC0000002u, result);
     }
 
     [Fact]
-    public void WalkEntitiesByCellIds_EmptyCellList_StillIncludesBuildingShells()
+    public void WalkEntitiesByCellIds_EmptyCellList_ExcludesBuildingShells()
     {
         var entities = new List<WorldEntity>
         {
             CellEnt(0x40000001u, 0xA9B40150u),
-            BuildingShell(0xC0000001u),
+            BuildingShell(0xC0000001u, 0xA9B40150u),
         };
 
         var result = WbDrawDispatcher.WalkEntitiesForTestByCellIds(
             entities, new HashSet<uint>(), set: WbDrawDispatcher.EntitySet.IndoorPass);
 
-        // Cell entity dropped (no cells in list); building shell still passes.
-        Assert.Single(result);
-        Assert.Contains(0xC0000001u, result);
+        Assert.Empty(result);
     }
 }