fix(chargen): Campaign CC CC6a review fix round — F1-F12

Addresses the CC6a dual-lens review (architectural PASS with reservations,
retail fidelity PASS with reservations, merge after F1/F2/F3).

F1 (BLOCKING) - AlternateSetup/setupId tested the wrong sentinel (0)
instead of retail's INVALID_DID (0xFFFFFFFF, CharGenState::GetSetupID
@0x005C5B22). A hair style storing that value would have been adopted as
a literal Setup id, nulling Get<Setup> and killing the whole preview.
Fixed both sites with a new InvalidDid constant; added two hand-built
tests plus an installed-DAT sweep of every hair style across all 26
heritage/gender combinations (869 selections, zero unresolved Setup ids).

F2 (BLOCKING) - TS-82's register row, ChargenClothingTable.cs's doc, and
the plan's ledger row all understated Undead's measured clothing-coverage
gap as "headgear/trousers/footwear" (3 slots) with a self-contradicting
"4 of 4 non-shirt slots" aside. Corrected everywhere to the true measured
ALL FOUR slots (headgear, trousers, shirt, footwear).

F3 (BLOCKING) - the palette-math "three independent sources" claim
overcounted: ACViewer's ClothingTableList.xaml.cs:97 computes a different
expression for a different problem, and its vendored PaletteSet.cs is
ACE's own file, not an independent implementation. Rewrote the evidence
paragraph in ChargenPalSetMath.cs to the two sources that actually hold
(decomp control flow + ACE's "Taken from acclient.c" port).

F4 (MEDIUM) - ChargenPreviewEntityBuilder.TryBuild did unlocked dat reads;
DatCollection is not thread-safe and every sibling dat-touching resolver
in this layer takes a shared datLock. Added a required datLock parameter;
every dat read now happens inside one lock, mirroring
RetailPaperdollPoseApplicator.Apply's shape.

F5 (LOW) - noted the pre-existing Streaming.LandblockBuildFactoryTests
timing flake in the ledger so a future session doesn't chase it.

F6 (LOW) - fixed ChargenPreviewCamera.cs's rotation doc, which cited a
nonexistent identifier in a dimensionally-wrong expression; corrected to
retail's actual DoRotation @0x0047CAC7 per-tick formula.

F7 (LOW-MEDIUM) - the TS-82 measurement was WriteLine-only; pinned with
real assertions (zero gaps for the 9 standard heritages, exactly the 4
measured Undead table ids on both genders). Kept the existing env-gated
skip pattern (confirmed house convention).

F8 (LOW) - the inner PalSet-miss loop recorded-and-continued past a miss;
retail's own loop returns immediately on a miss (~0x005A7B32), aborting
every remaining choice in that garment. Changed continue to break; added
a test proving a subsequent present PalSet is correctly not applied.

F9 (LOW) - fixed three dangling <see cref="...Compose"/> doc references
(the method is TryCompose).

F10 (LOW) - the packed (byte)(range/8) narrowing was unchecked; a real
NumColors of 2048 happened to wrap to the correct "whole palette" 0
sentinel by unchecked-cast accident. Replaced with explicit PackOffset/
PackNumColors helpers that document the 2048->0 equivalence deliberately
and throw on any other unrepresentable shape.

F11/F12 (LOW, CC6b scope) - noted in the plan's CC6b row: the second
m_alternateSetupID override source is unmodelled, and a shared
RetailHeldPose helper is worth extracting before a fourth consumer.

Test counts: Core.Tests 4772/1 skip (+5), Content.Tests 147/0 (+1),
App.Tests 5121/6 skips (unchanged; F5's named flake did not reproduce) -
zero failures, full solution Release build green.

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

src/AcDream.App/Rendering/ChargenPreviewCamera.cs

@@ -93,9 +93,13 @@ public sealed class ChargenPreviewCamera : ICamera
     /// (<c>gmCGAppearancePage::m_dRotationPerSec</c>, ctor pseudo-C
     /// ~137523-137524 / ~226652-226653: raw double bits low32=0x00000000,
     /// high32=0x40080000 → exactly 3.0 — the decompiler shows this cleanly,
-    /// no reconstruction needed). Consumed by CC6b's rotation controller as
-    /// <c>360f / RotationDegreesPerSecond</c> — NOT applied here; see this
-    /// class's own doc comment on why rotation is not a camera concern.
+    /// no reconstruction needed). Retail's own per-tick formula
+    /// (<c>gmCGAppearancePage::DoRotation @ 0x0047CA80</c>, pseudo-C
+    /// ~0x0047CAC7): <c>deltaDegrees = ((now - lastRotateTime) /
+    /// RotationSecondsPerRevolution) * 360</c> — CC6b's rotation controller
+    /// consumes this constant in exactly that shape, not as a
+    /// degrees-per-second rate. NOT applied here; see this class's own doc
+    /// comment on why rotation is not a camera concern.
     /// </summary>
     public const float RotationSecondsPerRevolution = 3.0f;