feat(render): Phase A8 RR5 — WbDrawDispatcher Draw(cellIds:) overload

Adds a new public overload accepting an explicit IReadOnlyCollection<uint>
cellIds (the camera-buildings' EnvCellIds) instead of a BFS-derived
visibility set. Used by RR7's IndoorPass to scope indoor rendering to the
camera-buildings' cells, not the full portal BFS (which causes Issues A+C).

Pure-data test helper WalkEntitiesForTestByCellIds added alongside the
production overload, mirroring the WalkEntitiesForTest pattern.

The overload internally delegates to the existing visibleCellIds path —
the dispatcher's semantic stays the same; only the caller's intent differs
(explicit cell list vs visibility-derived).

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

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

@@ -0,0 +1,90 @@
+// Phase A8 RR5 — verify WbDrawDispatcher.WalkEntitiesForTestByCellIds,
+// 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.
+// Outdoor scenery (no ParentCellId, not a shell) is excluded by EntitySet.IndoorPass.
+
+using System.Collections.Generic;
+using System.Numerics;
+using AcDream.App.Rendering.Wb;
+using AcDream.Core.World;
+using Xunit;
+
+namespace AcDream.Core.Tests.Rendering.Wb;
+
+public class WbDrawDispatcherCellIdsOverloadTests
+{
+    private static WorldEntity CellEnt(uint id, uint cellId) => new()
+    {
+        Id = id,
+        SourceGfxObjOrSetupId = 0x01000001u,
+        ParentCellId = cellId,
+        MeshRefs = new List<MeshRef> { new(0x01000001u, Matrix4x4.Identity) },
+        Position = Vector3.Zero,
+        Rotation = Quaternion.Identity,
+    };
+
+    private static WorldEntity OutdoorScenery(uint id) => new()
+    {
+        Id = id,
+        SourceGfxObjOrSetupId = 0x01000001u,
+        ParentCellId = null,
+        IsBuildingShell = false,
+        MeshRefs = new List<MeshRef> { new(0x01000001u, Matrix4x4.Identity) },
+        Position = Vector3.Zero,
+        Rotation = Quaternion.Identity,
+    };
+
+    private static WorldEntity BuildingShell(uint id) => new()
+    {
+        Id = id,
+        SourceGfxObjOrSetupId = 0x02000001u,
+        ParentCellId = null,
+        IsBuildingShell = true,
+        MeshRefs = new List<MeshRef> { new(0x01000001u, Matrix4x4.Identity) },
+        Position = Vector3.Zero,
+        Rotation = Quaternion.Identity,
+    };
+
+    [Fact]
+    public void WalkEntitiesByCellIds_IncludesOnlyEntitiesInListedCells()
+    {
+        var entities = new List<WorldEntity>
+        {
+            CellEnt(0x40000001u, 0xA9B40150u),  // in listed cells
+            CellEnt(0x40000002u, 0xA9B40151u),  // in listed cells
+            CellEnt(0x40000003u, 0xA9B40999u),  // OUT — not in list
+            BuildingShell(0xC0000001u),          // always included (IsBuildingShell)
+            OutdoorScenery(0xC0000002u),         // OUT — not a shell, not in cell list
+        };
+        var cellIds = new HashSet<uint> { 0xA9B40150u, 0xA9B40151u };
+
+        var result = WbDrawDispatcher.WalkEntitiesForTestByCellIds(
+            entities, cellIds, set: WbDrawDispatcher.EntitySet.IndoorPass);
+
+        Assert.Equal(3, result.Count);
+        Assert.Contains(0x40000001u, result);
+        Assert.Contains(0x40000002u, result);
+        Assert.Contains(0xC0000001u, result);
+        Assert.DoesNotContain(0x40000003u, result);
+        Assert.DoesNotContain(0xC0000002u, result);
+    }
+
+    [Fact]
+    public void WalkEntitiesByCellIds_EmptyCellList_StillIncludesBuildingShells()
+    {
+        var entities = new List<WorldEntity>
+        {
+            CellEnt(0x40000001u, 0xA9B40150u),
+            BuildingShell(0xC0000001u),
+        };
+
+        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);
+    }
+}