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.App/UI/ItemEquipRules.cs

@@ -0,0 +1,38 @@
+using AcDream.Core.Items;
+
+namespace AcDream.App.UI;
+
+internal static class ItemEquipRules
+{
+    // Retail CPlayerSystem::AutoWear / gmPaperDollUI inventory mask: 0x08007FFF.
+    public const EquipMask AutoWearMask =
+        EquipMask.HeadWear
+        | EquipMask.ChestWear
+        | EquipMask.AbdomenWear
+        | EquipMask.UpperArmWear
+        | EquipMask.LowerArmWear
+        | EquipMask.HandWear
+        | EquipMask.UpperLegWear
+        | EquipMask.LowerLegWear
+        | EquipMask.FootWear
+        | EquipMask.ChestArmor
+        | EquipMask.AbdomenArmor
+        | EquipMask.UpperArmArmor
+        | EquipMask.LowerArmArmor
+        | EquipMask.UpperLegArmor
+        | EquipMask.LowerLegArmor
+        | EquipMask.Cloak;
+
+    public static bool IsAutoWearItem(ClientObject item)
+        => (item.ValidLocations & AutoWearMask) != EquipMask.None;
+
+    public static EquipMask ResolvePaperdollDropWieldMask(ClientObject item, EquipMask targetMask)
+    {
+        if ((item.ValidLocations & targetMask) == EquipMask.None)
+            return EquipMask.None;
+
+        return IsAutoWearItem(item)
+            ? item.ValidLocations
+            : item.ValidLocations & targetMask;
+    }
+}