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>

src/AcDream.Core.Net/Messages/GameEvents.cs

@@ -336,11 +336,14 @@ public static class GameEvents
 
     public static WieldObject? ParseWieldObject(ReadOnlySpan<byte> payload)
     {
-        if (payload.Length < 12) return null;
+        if (payload.Length < 8) return null;
+        uint wielderGuid = payload.Length >= 12
+            ? BinaryPrimitives.ReadUInt32LittleEndian(payload.Slice(8))
+            : 0u;
         return new WieldObject(
             BinaryPrimitives.ReadUInt32LittleEndian(payload),
             BinaryPrimitives.ReadUInt32LittleEndian(payload.Slice(4)),
-            BinaryPrimitives.ReadUInt32LittleEndian(payload.Slice(8)));
+            wielderGuid);
     }
 
     /// <summary>0x0022 InventoryPutObjInContainer: server puts item into container slot.