feat(D.5.1): persist PlayerDescription shortcuts (were parsed then discarded)

Add optional `onShortcuts` callback to `GameEventWiring.WireAll`; invoke
it with `parsed.Shortcuts` after the inventory/equipped loops in the
PlayerDescription handler.  `GameWindow` holds the list in a new
`Shortcuts` property (initialized to empty) so the toolbar (D.5.1 Task 5)
can read hotbar slots without keeping a parser reference.  Existing callers
compile unchanged — the parameter defaults to null.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/AcDream.App/Rendering/GameWindow.cs

@@ -596,6 +596,9 @@ public sealed class GameWindow : IDisposable
     public readonly AcDream.Core.Spells.SpellTable SpellTable = LoadSpellTable();
     public readonly AcDream.Core.Spells.Spellbook SpellBook = null!;
     public readonly AcDream.Core.Items.ItemRepository Items = new();
+    /// <summary>Persisted hotbar shortcuts from the last PlayerDescription (D.5.1 toolbar source).</summary>
+    public IReadOnlyList<AcDream.Core.Net.Messages.PlayerDescriptionParser.ShortcutEntry> Shortcuts { get; private set; }
+        = System.Array.Empty<AcDream.Core.Net.Messages.PlayerDescriptionParser.ShortcutEntry>();
     // Issue #5 — caches CreatureProfile.{Stamina, Mana, *Max} from
     // PlayerDescription so the Vitals HUD can render those bars.
     // Issue #6 — wired to SpellBook so GetMaxApprox folds enchantment
@@ -2309,7 +2312,8 @@ public sealed class GameWindow : IDisposable
                             _lastSeenRunSkill, _lastSeenJumpSkill);
                         Console.WriteLine($"player: applied server skills run={_lastSeenRunSkill} jump={_lastSeenJumpSkill}");
                     }
-                });
+                },
+                onShortcuts: list => Shortcuts = list);
 
             // Phase I.7: subscribe to CombatState events and emit
             // retail-faithful "You hit X for Y damage" chat lines into