cull(engine-cleanup): pass-8 phase-2 cascade round 2

[trim] fully-unreachable files deleted: 3
[trim] files edited: 21, files deleted: 0, nodes removed: 38
[type-trim] files edited: 3, types removed: 3

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

SVSim.BattleEngine/Shim/GodObjects/GodObjects.cs

@@ -95,9 +95,6 @@ public partial class UIManager : UnityEngine.MonoBehaviour
 
 namespace Wizard
 {
-    // RankWinnerReward, CardDestructTask, CardCreateTask, MissionInfoTask already exist
-    // in the copied set (declared in other files) -- only these three were missing.
-    public partial class MailTopTask { }
     public partial class DeckUpdateTask { }
     // UIManager no-op return types (empty stubs; methods returning them return null)
     public partial class LoadingViewManager { }