feat(main-window): wire Lender + handler.Draw() (A2, MessageList popups)

A2 completes the deferred Lender-cycle from A1 and addresses the
handler.Draw() gap identified in I code-quality-review:

- MainWindow ctor takes Lender<PayloadHandler> as new param (DI-reg
  extended in PluginHostFactory); _handlerLender.ResetCounter() called
  at top of Draw() as primary pool-reset path (InputPreview has the
  secondary defensive fallback for MainWindow-closed edge case)

- MessageList.DrawHandlerPopups() new passthrough method
  (=> _handler?.Draw()) provides the per-frame popup-tick that
  PayloadHandler needs to render the right-click context popup;
  MainWindow.Draw() calls it after the message-list body renders

Without this fix, right-clicking a player/item/status in the chat log
would silently fail to open a popup (handler.Draw() never fired for the
MessageList's _handler). Phase 3 smoke steps 3/4/5 unblocked.

Polish-Sweep + Smoke-Gate are the last cycle-tasks.

HellionChat/Ui/Windows/MainWindow.cs

@@ -2,6 +2,7 @@ using System.Numerics;
 using Dalamud.Bindings.ImGui;
 using Dalamud.Interface.Utility.Raii;
 using Dalamud.Interface.Windowing;
+using HellionChat.Util;
 
 namespace HellionChat.Ui.Windows;
 
@@ -26,6 +27,7 @@ internal sealed class MainWindow : Window
     private readonly Components.MessageList _messages;
     private readonly Components.InputBar _input;
     private readonly Components.StatusBar _status;
+    private readonly Lender<PayloadHandler> _handlerLender;
 
     private Tab? _activeTab;
 
@@ -38,7 +40,8 @@ internal sealed class MainWindow : Window
         Components.Sidebar sidebar,
         Components.MessageList messages,
         Components.InputBar input,
-        Components.StatusBar status
+        Components.StatusBar status,
+        Lender<PayloadHandler> handlerLender
     )
         : base($"{Plugin.PluginName}###hellion-main")
     {
@@ -47,6 +50,7 @@ internal sealed class MainWindow : Window
         _messages = messages;
         _input = input;
         _status = status;
+        _handlerLender = handlerLender;
 
         Size = new Vector2(DefaultWidth, DefaultHeight);
         SizeCondition = ImGuiCond.FirstUseEver;
@@ -92,6 +96,9 @@ internal sealed class MainWindow : Window
             LastViewport = ImGui.GetWindowViewport().Handle;
         }
 
+        // Primary pool-reset path; InputPreview has a defensive fallback for the MainWindow-closed edge case.
+        _handlerLender.ResetCounter();
+
         // First-frame seed: the active tab defaults to the first persisted
         // tab so the message list isn't empty on a clean session.
         if (_activeTab is null && Plugin.Config.Tabs.Count > 0)
@@ -105,6 +112,7 @@ internal sealed class MainWindow : Window
                 DrawBody();
         }
 
+        _messages.DrawHandlerPopups();
         _status.Draw(_activeTab);
     }