feat(ui): D.2b item interaction + retail cursors + live character sheet

Lands the codex-worktree D.2b stream plus the extraction the 2026-07-02
UI architecture review mandated before commit:

- ItemInteractionController: single owner of double-click use/equip/
  container-open, targeted-use mode (health kits), drag-out drop;
  toolbar shortcut drags don't drop the real item. ItemEquipRules for
  multi-slot (coat) coverage via equip masks.
- Cursor phase: CursorFeedbackController (semantic priority chain:
  drag > resize > window-move > target-mode > text) + RetailCursorCatalog
  (enums 0x27/0x28/0x29, hotspot 14,14; ClientUISystem::UpdateCursorState
  0x00564630) resolved through the portal EnumIDMap chain by
  RetailCursorResolver; RetailCursorManager applies dat cursor art to the
  OS cursor. Register row AP-72 covers the OS standard-cursor fallback.
- Character window goes live: CharacterSheetProvider owns sheet assembly,
  XP-curve/raise-cost math and the raise flow — extracted out of
  GameWindow per Code Structure Rule 1 instead of committing the ~430-line
  feature body there. Optimistic XP/credit debits go through eventful
  store APIs (new ClientObjectTable.UpdateInt64Property +
  LocalPlayerState.DebitIntProperty/DebitInt64Property) instead of raw
  property-dictionary writes; register row AP-73 covers the still-missing
  raise ledger (#163).
- RetailWindowFrame: the shared nine-slice window mount recipe; the
  character window uses it, remaining windows migrate via #164.
- Status-bar buttons toggle inventory/character windows; retail row-major
  backpack ordering; WorldSession.SendUseWithTarget + raise/train sends.

GameWindow shrinks 14,214 -> 13,877 lines despite the new features; the
sheet/raise logic is unit-tested in CharacterSheetProviderTests instead
of trapped in the god object. Build green; full suite 3,286 tests pass.

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

tests/AcDream.App.Tests/UI/Layout/LayoutImporterTests.cs

@@ -40,6 +40,22 @@ public class LayoutImporterTests
     /// draws nothing until a controller binds its <c>LinesProvider</c>);
     /// the Type-3 must also be present.
     /// </summary>
+    [Fact]
+    public void BuildFromInfos_StampsDatElementId_OnRootAndItemList()
+    {
+        const uint RootId = 0x100005F9u;
+        const uint ListId = 0x100001C6u;
+
+        var root = new ElementInfo { Id = RootId, Type = 3, Width = 160, Height = 58 };
+        var itemList = new ElementInfo { Id = ListId, Type = 0x10000031u, X = 5, Y = 5, Width = 72, Height = 72 };
+
+        var tree = LayoutImporter.BuildFromInfos(root, new[] { itemList }, NoTex, null);
+
+        Assert.Equal(RootId, tree.Root.DatElementId);
+        var found = Assert.IsType<UiItemList>(tree.FindElement(ListId));
+        Assert.Equal(ListId, found.DatElementId);
+    }
+
     [Fact]
     public void BuildFromInfos_Type12Child_IsSkipped_Type3Present()
     {