refactor(runtime): own inventory transaction state

Move the retail one-request-at-a-time gate, shared use busy references, external-container state, item mana, shortcuts, and desired-component snapshots into one Runtime-owned graph over J3's exact ClientObjectTable. Retained UI and session routing now borrow that owner; reset and shutdown preserve the existing order while failure/reentrancy tests protect the transaction boundary.

Co-authored-by: Codex <codex@openai.com>

src/AcDream.App/Composition/SessionPlayerComposition.cs

@@ -72,8 +72,7 @@ internal sealed record SessionPlayerDependencies(
     ViewportAspectState ViewportAspect,
     PlayerApproachCompletionState PlayerApproachCompletions,
     PlayerCharacterOptionsState CharacterOptions,
-    ShortcutSnapshotState Shortcuts,
-    DesiredComponentSnapshotState DesiredComponents,
+    RuntimeInventoryState Inventory,
     PointerPositionState PointerPosition,
     DispatcherMovementInputSource MovementInput,
     IInputCaptureSource InputCapture,
@@ -88,8 +87,6 @@ internal sealed record SessionPlayerDependencies(
     RuntimeCommunicationState Communication,
     LocalPlayerState LocalPlayer,
     Spellbook Spellbook,
-    ItemManaState ItemMana,
-    ExternalContainerState ExternalContainers,
     TransferableResourceSlot<PortalTunnelPresentation> PortalTunnelFallback,
     Action<string> Log);
 
@@ -802,16 +799,13 @@ internal sealed class SessionPlayerCompositionPhase
                 d.PlayerController,
                 d.PlayerSkills,
                 d.WorldOrigin,
-                d.CharacterOptions,
-                d.Shortcuts,
-                d.DesiredComponents),
+                d.CharacterOptions),
             new LiveSessionDomainRuntime(
                 d.EntityObjects,
                 d.LocalPlayer,
                 d.Spellbook,
                 d.Combat,
-                d.ItemMana,
-                d.ExternalContainers,
+                d.Inventory,
                 d.Communication),
             new LiveSessionUiRuntime(
                 interaction.RetainedUi?.Runtime,