fix(chargen): Campaign CC gate round 1 closeout — Group 3: round review fixes (F4-F11, F14, F16)

The remaining code-bearing findings from the round review, F4-F16 minus
the doc-only items (batched separately):

- F4: three client-wide UiButton corpus sweeps (LabelBox path — exactly
  the 4 Town buttons, confined to chargen; conflicting custom-selection-
  pair + standard Normal/Highlight media — zero found, no gate
  tightening needed; per-state label-color map — 209 matches beyond
  chargen, confirming AP-222's mechanism has always been broadly active
  since it shipped generically in DatWidgetFactory).
- F5/F6: LayoutImporter's Batch C un-consumed-children carve-out now
  honors a child's own AuthoredInvisible flag (a narrow honor scoped to
  exactly that carve-out, not the general #408 client-wide one) — the
  chat transcript's new-text indicator (0x1000048C) was building as a
  visible phantom element retail never shows; verified both directions
  against the gold-frame pieces, which do not author Invisible.
- F7: BoundedProcessOutputCapture.AppendLine combines the line text and
  its trailing newline into one buffer and one file open/write/close
  instead of two.
- F9: corrected a stale comment in RuntimeSettingsTargets — #407 split
  DisplayModeCatalog's Resolutions/WindowedResolutions in two, so the
  fullscreen validator's own narrower list is now DELIBERATELY different
  from the Config dropdown's fuller offering, not the "must match" bug
  the comment described.
- F10: documented (not changed) why the LabelBox path's default 3px
  inset and the face-relative +4px gap in DatWidgetFactory.BuildButton
  are deliberately different numbers — neither carries a retail
  citation, and moving either to match the other would be an unfounded
  guess on a button that currently works correctly.
- F11: Heritage/Profession/Summary/Town description pages now compose
  DatRichText.Compose's result ONCE inside their already revision-gated
  Refresh, caching the built line list instead of re-wrapping on every
  draw call.
- F14: documented (not changed) why PrivateEntityViewportRenderer's
  _animatedIds set carrying a reserved-but-never-drawn backdrop id is
  harmless — BuildDrawEntities already excludes a null/empty backdrop
  from the actual draw list, so the id is never looked up.
- F16: the Summary preview now uses its own render-id pair
  (SummaryPreviewRenderId/SummaryPreviewBackdropRenderId, 0xDA11D035/
  0xDA11D036) instead of sharing the Appearance page's
  (0xDA11D032/0xDA11D034) — confirmed by tracing
  FixedEntityTextureOwnerLease through TextureCache to
  CompositeTextureArrayCache's shared owner tracker that both pages'
  previews share ONE process-wide TextureCache, so sharing render ids
  was a real cross-page texture-release collision (either page's own
  re-dress or disposal could release the OTHER page's still-active
  textures), not a theoretical one.

F3's own register bookkeeping (AP-229 addendum) and F12's register/AD
header-count corrections land in the docs-only commit alongside F15.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

tests/AcDream.App.Tests/Rendering/ChargenPreviewEntityBuilderTests.cs

@@ -66,6 +66,57 @@ public sealed class ChargenPreviewEntityBuilderTests
         _out.WriteLine($"setup=0x{appearance.SetupId:X8} meshRefs={entity.MeshRefs.Count} subPalettes={entity.PaletteOverride.SubPalettes.Count}");
     }
 
+    /// <summary>
+    /// F16 (Campaign CC gate round 1 closeout): the Appearance and Summary
+    /// pages must stamp DIFFERENT <see cref="AcDream.Core.World.WorldEntity.Id"/>
+    /// values on their preview entities — both feed the SAME shared
+    /// <c>TextureCache</c> owner-tracking key
+    /// (<c>ChargenPreviewEntityBuilder.SummaryPreviewRenderId</c>'s own doc
+    /// has the full collision trace). Pins BOTH halves: the constants
+    /// themselves are distinct, AND the explicit <c>renderId</c> parameter
+    /// actually reaches the built entity (not silently ignored).
+    /// </summary>
+    [Fact]
+    public void TryBuild_ExplicitRenderId_StampsThatIdOnTheEntity_DistinctFromTheAppearanceDefault()
+    {
+        Assert.NotEqual(
+            ChargenPreviewEntityBuilder.PreviewRenderId,
+            ChargenPreviewEntityBuilder.SummaryPreviewRenderId);
+        Assert.NotEqual(
+            ChargenPreviewEntityBuilder.PreviewBackdropRenderId,
+            ChargenPreviewEntityBuilder.SummaryPreviewBackdropRenderId);
+
+        string? datDir = CornerFloodReplayTests.ResolveDatDir();
+        if (datDir is null) { _out.WriteLine("SKIP: dats unavailable"); return; }
+
+        using var dats = new DatCollection(datDir, DatAccessType.Read);
+        using var adapter = new DatCollectionAdapter(dats);
+
+        ChargenOptions options = ChargenTableReader.Load(adapter);
+        Assert.True(options.TryGetHeritage(1u, out ChargenHeritageOptions? aluvian)); // Aluvian.
+        Assert.True(aluvian!.GendersByKey.TryGetValue(1, out ChargenGenderOptions? male));
+
+        var catalog = new ChargenAppearanceCatalog(adapter);
+        ChargenAppearanceSelection selection = ChargenAppearanceSelection.Default with
+        {
+            HairStyle = male!.HairStyles.Count > 0 ? 0u : ChargenAppearanceSelection.Unset,
+            SkinShade = 0.5,
+        };
+
+        bool composed = ChargenAppearanceFactory.TryCompose(
+            options, 1u, 1, selection, catalog, catalog, out ChargenAppearanceResult appearance);
+        Assert.True(composed);
+
+        var animations = new RetailAnimationLoader(adapter);
+        var entity = ChargenPreviewEntityBuilder.TryBuild(
+            adapter, animations, appearance, heritageId: 1u, Quaternion.Identity, new object(),
+            renderId: ChargenPreviewEntityBuilder.SummaryPreviewRenderId);
+
+        Assert.NotNull(entity);
+        Assert.Equal(ChargenPreviewEntityBuilder.SummaryPreviewRenderId, entity!.Id);
+        Assert.NotEqual(ChargenPreviewEntityBuilder.PreviewRenderId, entity.Id);
+    }
+
     [Fact]
     public void TryBuild_UnknownSetupId_ReturnsNull()
     {
@@ -317,6 +368,36 @@ public sealed class ChargenPreviewEntityBuilderTests
         _out.WriteLine($"backdropSetup=0x{aluvian.EnvironmentSetupId:X8} meshRefs={entity.MeshRefs.Count}");
     }
 
+    /// <summary>F16 (Campaign CC gate round 1 closeout): the backdrop's own
+    /// explicit <c>renderId</c> parameter reaches the built entity, the
+    /// same shape as <see cref="TryBuild_ExplicitRenderId_StampsThatIdOnTheEntity_DistinctFromTheAppearanceDefault"/>
+    /// pins for the main preview entity.</summary>
+    [Fact]
+    public void TryBuildBackdrop_ExplicitRenderId_StampsThatIdOnTheEntity()
+    {
+        string? datDir = CornerFloodReplayTests.ResolveDatDir();
+        if (datDir is null) { _out.WriteLine("SKIP: dats unavailable"); return; }
+
+        using var dats = new DatCollection(datDir, DatAccessType.Read);
+        using var adapter = new DatCollectionAdapter(dats);
+
+        ChargenOptions options = ChargenTableReader.Load(adapter);
+        Assert.True(options.TryGetHeritage(1u, out ChargenHeritageOptions? aluvian)); // Aluvian.
+        if (aluvian!.EnvironmentSetupId == 0u)
+        {
+            _out.WriteLine("SKIP: installed dat's Aluvian heritage authors no EnvironmentSetupId.");
+            return;
+        }
+
+        var entity = ChargenPreviewEntityBuilder.TryBuildBackdrop(
+            adapter, aluvian.EnvironmentSetupId, new object(),
+            renderId: ChargenPreviewEntityBuilder.SummaryPreviewBackdropRenderId);
+
+        Assert.NotNull(entity);
+        Assert.Equal(ChargenPreviewEntityBuilder.SummaryPreviewBackdropRenderId, entity!.Id);
+        Assert.NotEqual(ChargenPreviewEntityBuilder.PreviewBackdropRenderId, entity.Id);
+    }
+
     /// <summary>Retail's own gate at 0x004eed29 (<c>if (eax_32 != INVALID_DID.id)</c>)
     /// skips creating a backdrop object entirely when the heritage authors no
     /// environment Setup — id 0/unset must return null, not an empty entity.</summary>