feat(ui): port retail toolbar ammo count

Resolve stacked thrown weapons versus separately equipped missile ammo exactly like gmToolbarUI, normalize a zero stack to one, and refresh the authored missile indicator from equipment and stack events. Keep the decision in pure Core with retained and real-DAT conformance coverage.

Co-Authored-By: Codex <codex@openai.com>

src/AcDream.App/UI/RetailUiRuntime.cs

@@ -390,7 +390,8 @@ public sealed class RetailUiRuntime : IDisposable
             selectItem: guid => b.Selection.Select(guid, SelectionChangeSource.Toolbar),
             selectedObjectId: () => b.Selection.SelectedObjectId ?? 0u,
             playerGuid: b.PlayerGuid,
-            sendPutItemInContainer: b.SendPutItemInContainer);
+            sendPutItemInContainer: b.SendPutItemInContainer,
+            ammoFont: _bindings.Assets.DefaultFont);
         ToolbarInputController = new ToolbarInputController(ToolbarController, b.Selection);
         SelectedObjectController = Layout.SelectedObjectController.Bind(
             layout,